Cab Roof Lights - The 1947 - Present Chevrolet & GMC Truck Message Board Network

prg machine · 10-27-2022, 06:26 PM

I am interested in putting some Clearance Lights on my K-20. I have numerous questions:

1 Is there ample clearance between the conventional, non raised, outer roof skin and the inner Cab panel for drilling holes and routing wiring?

2 Can someone post dimensions from Center of the roof, where the center light mounts, to the center of each adjacent light closest to the center light, and the distance from center, or the outside edge of the roof, to the 2 lights closest to the outside? I would also need a dimension from the front edge of Cab to the front edge of the light base.

3 How do the Pacer aftermarket lights compare to the original Yankee 77s? Are they all Plastic? I've read that most aftermarket base gaskets are cheap foam and not quality rubber like the original. They seem awfully cheaply priced to be of any quality.

4 The ones that NAPA sells are over 50.00 dollars, but look like the real thing, can't tell if the bases are Chrome metal or plastic. Anyone know about these?

Thank you!

CG · 10-27-2022, 06:32 PM

Like mentioned on this same post over on the burb side they are called Yankee 77 and yes there is room. Here is a link to a ton of posts over the years on this subject ... https://www.google.com/search?q=cab+...client=gws-wiz

Another place to look for these are decent sized truck stops if you have one in your area.

Here is a pic of a placement sheet from GM for holes for the lights ..

prg machine · 10-27-2022, 06:34 PM

Thanks for the diagram!!!
I would have never realized that the 2 outside lights are set at an angle.
Yes, I mistakenly put my post in the wrong forum originally.

**LockDoc** · 10-27-2022, 07:00 PM

Quote:

Originally Posted by prg machine

Thanks for the diagram!!!
I would have never realized that the 2 outside lights are set at an angle.
Yes, I mistakenly put my post in the wrong forum originally.

One of the instruction sheets I have show all of the lights pointing straight forward. That is the way I chose to install mine.

http://67-72chevytrucks.com/vboard/s...=829820&page=5

Post #119, 120, 126, 127, & 131

LockDoc

**Johnl48** · 10-27-2022, 07:34 PM

Put them on mine. Just followed measurements in the assembly manual. Hardest part was getting the wires up there from the B pillar

prg machine · 10-28-2022, 01:10 PM

In order to run wires up to the lights and go through the Cab Pillar, where is the access? Inside the Cowl? Up through under the Dash?

CG · 10-28-2022, 01:27 PM

Here is a link, its among all the links I posted in the board search for you. LocDoc also covered it in the thread he posted

https://www.youtube.com/watch?v=-53fdPXgVLA

prg machine · 10-28-2022, 04:10 PM

Thanks again!!

prg machine · 10-30-2022, 12:17 AM

I felt around up under the Dash adjacent to the Pillar on the Driver's and Passengers side and I can't feel a hole anywhere. Used some welding wire and couldn't push it up into the pillar either. I had thought about running the wiring down the Passenger's Side Pillar since I want to eventually drill the Driver's side for a Spotlight.
Posted via Mobile Device

**Johnl48** · 10-30-2022, 08:28 AM

Quote:

Originally Posted by prg machine

I felt around up under the Dash adjacent to the Pillar on the Driver's and Passengers side and I can't feel a hole anywhere. Used some welding wire and couldn't push it up into the pillar either. I had thought about running the wiring down the Passenger's Side Pillar since I want to eventually drill the Driver's side for a Spotlight.
Posted via Mobile Device

If it's not a cab light roof there is no hole. You have to go up the B pillar. Follow the dome light wires. Now getting the wire to the front is the hard part. I had to fish welding wire via the headliner trim holes inside

chewychevy67 · 10-30-2022, 09:35 AM

This is the hole in the pillar. I would have assumed they all had this hole but mine is a cab light truck. They re the reason my roof had to be replaced because of dents and when they were welded up it warped my panel. My new roof will not be getting them on it.

**sloGMC** · 10-30-2022, 10:58 AM

Quote:

Originally Posted by prg machine

I felt around up under the Dash adjacent to the Pillar on the Driver's and Passengers side and I can't feel a hole anywhere. Used some welding wire and couldn't push it up into the pillar either.
Posted via Mobile Device

I believe there is an unpunched hole just above the driver's kickpanel. If you have an assembly manual the cab-light drawing should help you locate it. I added cab lights to my '71 (also not originally equipped w/ U01 markers) and had no issues fishing wire through the A pillar.
There are some other threads that mention that removing the rear-view mirror and sunvisors to assist in pulling wire through. I would also recommend that; the screws from the rear-view mirror mount love to catch wires and it's easiest to fish the wire in a two-step process. I fed half of the harness through the sunvisor to the rest of the roof, and then the other half of wiring through the drivers sunvisor down through the kickpanel.

I also don't ever want to do it again so I wrapped everything with some wire braid and put heat shrink on all the splices.

prg machine · 10-30-2022, 11:01 AM

Quote:

Originally Posted by chewychevy67

This is the hole in the pillar. I would have assumed they all had this hole but mine is a cab light truck. They re the reason my roof had to be replaced because of dents and when they were welded up it warped my panel. My new roof will not be getting them on it.

Could you post a picture of where the access hole is at the bottom of the pillar behind the Dash on the Driver's side?
Also, is there an opening behind the Dash on the Passenger's side?
Thanks

**Wrenchbender Ret** · 10-30-2022, 11:06 AM

I used black wire & tucked it in the windshield rubber. You couldn't see it at all.
I put an extra fuse in the circuit wire leading to it. I put a low amp fuse so it there was a short in all that wiring & lights it would not kick out the tail lights.

George

**sloGMC** · 10-30-2022, 11:26 AM

Quote:

Originally Posted by prg machine

Could you post a picture of where the access hole is at the bottom of the pillar behind the Dash on the Driver's side?

Post 10 of this thread has a picture of the roof lights from the assembly manual. Your cab will not have a pre-punched hole. You drill a hole above the kick panel in about the area shown in the picture. Your gauge cluster probably needs to be removed do this.

prg machine · 10-30-2022, 12:17 PM

Quote:

Originally Posted by sloGMC

Post 10 of this thread has a picture of the roof lights from the assembly manual. Your cab will not have a pre-punched hole. You drill a hole above the kick panel in about the area shown in the picture. Your gauge cluster probably needs to be removed do this.

Curious here, how big is the hole in the Cab Roof drilled to attach the connectors and fish the wires through to the light?

chewychevy67 · 10-30-2022, 01:11 PM

This is a different truck cab i had done and I made the the hole a bit larger on it cause I added door locks and such but this is where it's located. The stock hole is 1" in diameter. From here it goes straight upthe Pilar to the roof. The wire plugs into the headlight switch.

prg machine · 10-30-2022, 04:43 PM

So how big is the hole through the Cab Roof for the Pig Tail on the Lights?

chewychevy67 · 10-30-2022, 05:27 PM

I don't know. My roof has been welded back together already so I can't measure. Probably 1/2 inch or so.

Bigdav160 · 10-30-2022, 05:49 PM

On my Suburban the rear A/C wiring goes through the same hole. It's about 1/2"

prg machine · 10-30-2022, 11:35 PM

Anyway, sounds kike a "fishing" experience getting the wires to route through.
Thanks everyone

prg machine · 10-31-2022, 04:42 PM

There's a guy selling reproduction Yankee 77s on Ebay, so I ordered a set, a little over 60 dollars for the set of 5.
LED

prg machine · 10-31-2022, 04:46 PM

https://www.ebay.com/itm/15523002174...Bk9SR9jPyfyFYQ

10-27-2022, 06:32 PM	#2
CG BlahBlahBlah Join Date: Feb 2002 Location: Wa. Posts: 19,791	Re: Cab Roof Lights Like mentioned on this same post over on the burb side they are called Yankee 77 and yes there is room. Here is a link to a ton of posts over the years on this subject ... https://www.google.com/search?q=cab+...client=gws-wiz Another place to look for these are decent sized truck stops if you have one in your area. Here is a pic of a placement sheet from GM for holes for the lights .. __________________ … … … … … … … … ... … … … … … … … … … … …

10-27-2022, 06:34 PM	#3
prg machine Registered User Join Date: Jun 2007 Location: oregon Posts: 1,069	Re: Cab Roof Lights Thanks for the diagram!!! I would have never realized that the 2 outside lights are set at an angle. Yes, I mistakenly put my post in the wrong forum originally. __________________ 69 K-20 cloned to a 67 with front clip and some other stuff. 383 .040 over Crane roller cam lifters and rockers ,1.6 intake ratio, Open chamber heads, 9.5-1 compression ratio, 2.02 intake valves , Edelbrock performer Air Gap manifold Carter AFB performer 750cfm, MSD ignition, SM465 NP205 4.10 gears:

10-27-2022, 07:34 PM	#5
Johnl48 Senior Member Join Date: Jun 2021 Location: West milford nj Posts: 323	Re: Cab Roof Lights Put them on mine. Just followed measurements in the assembly manual. Hardest part was getting the wires up there from the B pillar

10-28-2022, 01:10 PM	#6
prg machine Registered User Join Date: Jun 2007 Location: oregon Posts: 1,069	Re: Cab Roof Lights In order to run wires up to the lights and go through the Cab Pillar, where is the access? Inside the Cowl? Up through under the Dash? __________________ 69 K-20 cloned to a 67 with front clip and some other stuff. 383 .040 over Crane roller cam lifters and rockers ,1.6 intake ratio, Open chamber heads, 9.5-1 compression ratio, 2.02 intake valves , Edelbrock performer Air Gap manifold Carter AFB performer 750cfm, MSD ignition, SM465 NP205 4.10 gears:

10-28-2022, 01:27 PM	#7
CG BlahBlahBlah Join Date: Feb 2002 Location: Wa. Posts: 19,791	Re: Cab Roof Lights Here is a link, its among all the links I posted in the board search for you. LocDoc also covered it in the thread he posted https://www.youtube.com/watch?v=-53fdPXgVLA __________________ … … … … … … … … ... … … … … … … … … … … …

10-27-2022, 06:26 PM	#1
prg machine Registered User Join Date: Jun 2007 Location: oregon Posts: 1,069	Cab Roof Lights I am interested in putting some Clearance Lights on my K-20. I have numerous questions: 1 Is there ample clearance between the conventional, non raised, outer roof skin and the inner Cab panel for drilling holes and routing wiring? 2 Can someone post dimensions from Center of the roof, where the center light mounts, to the center of each adjacent light closest to the center light, and the distance from center, or the outside edge of the roof, to the 2 lights closest to the outside? I would also need a dimension from the front edge of Cab to the front edge of the light base. 3 How do the Pacer aftermarket lights compare to the original Yankee 77s? Are they all Plastic? I've read that most aftermarket base gaskets are cheap foam and not quality rubber like the original. They seem awfully cheaply priced to be of any quality. 4 The ones that NAPA sells are over 50.00 dollars, but look like the real thing, can't tell if the bases are Chrome metal or plastic. Anyone know about these? Thank you! __________________ 69 K-20 cloned to a 67 with front clip and some other stuff. 383 .040 over Crane roller cam lifters and rockers ,1.6 intake ratio, Open chamber heads, 9.5-1 compression ratio, 2.02 intake valves , Edelbrock performer Air Gap manifold Carter AFB performer 750cfm, MSD ignition, SM465 NP205 4.10 gears: Last edited by prg machine; 10-27-2022 at 06:29 PM. Reason: More information

10-28-2022, 04:10 PM	#8
prg machine Registered User Join Date: Jun 2007 Location: oregon Posts: 1,069	Re: Cab Roof Lights Thanks again!! __________________ 69 K-20 cloned to a 67 with front clip and some other stuff. 383 .040 over Crane roller cam lifters and rockers ,1.6 intake ratio, Open chamber heads, 9.5-1 compression ratio, 2.02 intake valves , Edelbrock performer Air Gap manifold Carter AFB performer 750cfm, MSD ignition, SM465 NP205 4.10 gears:

10-30-2022, 12:17 AM	#9
prg machine Registered User Join Date: Jun 2007 Location: oregon Posts: 1,069	Re: Cab Roof Lights I felt around up under the Dash adjacent to the Pillar on the Driver's and Passengers side and I can't feel a hole anywhere. Used some welding wire and couldn't push it up into the pillar either. I had thought about running the wiring down the Passenger's Side Pillar since I want to eventually drill the Driver's side for a Spotlight. Posted via Mobile Device

10-30-2022, 09:35 AM	#11
chewychevy67 Registered User Join Date: Jan 2010 Location: Here Posts: 5,426	Re: Cab Roof Lights This is the hole in the pillar. I would have assumed they all had this hole but mine is a cab light truck. They re the reason my roof had to be replaced because of dents and when they were welded up it warped my panel. My new roof will not be getting them on it. Attached Images

10-30-2022, 11:06 AM	#14
Wrenchbender Ret Registered User Join Date: Oct 2005 Location: Overland Park, Ks. Posts: 5,193	Re: Cab Roof Lights I used black wire & tucked it in the windshield rubber. You couldn't see it at all. I put an extra fuse in the circuit wire leading to it. I put a low amp fuse so it there was a short in all that wiring & lights it would not kick out the tail lights. George

10-30-2022, 01:11 PM	#17
chewychevy67 Registered User Join Date: Jan 2010 Location: Here Posts: 5,426	Re: Cab Roof Lights This is a different truck cab i had done and I made the the hole a bit larger on it cause I added door locks and such but this is where it's located. The stock hole is 1" in diameter. From here it goes straight upthe Pilar to the roof. The wire plugs into the headlight switch. Attached Images

10-30-2022, 04:43 PM	#18
prg machine Registered User Join Date: Jun 2007 Location: oregon Posts: 1,069	Re: Cab Roof Lights So how big is the hole through the Cab Roof for the Pig Tail on the Lights? __________________ 69 K-20 cloned to a 67 with front clip and some other stuff. 383 .040 over Crane roller cam lifters and rockers ,1.6 intake ratio, Open chamber heads, 9.5-1 compression ratio, 2.02 intake valves , Edelbrock performer Air Gap manifold Carter AFB performer 750cfm, MSD ignition, SM465 NP205 4.10 gears:

10-30-2022, 05:27 PM	#19
chewychevy67 Registered User Join Date: Jan 2010 Location: Here Posts: 5,426	Re: Cab Roof Lights I don't know. My roof has been welded back together already so I can't measure. Probably 1/2 inch or so.

10-30-2022, 05:49 PM	#20
Bigdav160 Registered User Join Date: Apr 2011 Location: Klein Texas Posts: 3,852	Re: Cab Roof Lights On my Suburban the rear A/C wiring goes through the same hole. It's about 1/2" __________________ My Classics: '72 K20 Suburban + '65 Dodge Town Wagon '72 Corvette Roadster +'67 Corvette Roadster '73 Z-28 Camaro '63 Ford SWB Uni Pickup '50 Ford Coupe

10-30-2022, 11:35 PM	#21
prg machine Registered User Join Date: Jun 2007 Location: oregon Posts: 1,069	Re: Cab Roof Lights Anyway, sounds kike a "fishing" experience getting the wires to route through. Thanks everyone __________________ 69 K-20 cloned to a 67 with front clip and some other stuff. 383 .040 over Crane roller cam lifters and rockers ,1.6 intake ratio, Open chamber heads, 9.5-1 compression ratio, 2.02 intake valves , Edelbrock performer Air Gap manifold Carter AFB performer 750cfm, MSD ignition, SM465 NP205 4.10 gears:



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10-31-2022, 04:42 PM	#22
prg machine Registered User Join Date: Jun 2007 Location: oregon Posts: 1,069	Re: Cab Roof Lights There's a guy selling reproduction Yankee 77s on Ebay, so I ordered a set, a little over 60 dollars for the set of 5. LED __________________ 69 K-20 cloned to a 67 with front clip and some other stuff. 383 .040 over Crane roller cam lifters and rockers ,1.6 intake ratio, Open chamber heads, 9.5-1 compression ratio, 2.02 intake valves , Edelbrock performer Air Gap manifold Carter AFB performer 750cfm, MSD ignition, SM465 NP205 4.10 gears:

10-31-2022, 04:46 PM	#23
prg machine Registered User Join Date: Jun 2007 Location: oregon Posts: 1,069	Re: Cab Roof Lights https://www.ebay.com/itm/15523002174...Bk9SR9jPyfyFYQ __________________ 69 K-20 cloned to a 67 with front clip and some other stuff. 383 .040 over Crane roller cam lifters and rockers ,1.6 intake ratio, Open chamber heads, 9.5-1 compression ratio, 2.02 intake valves , Edelbrock performer Air Gap manifold Carter AFB performer 750cfm, MSD ignition, SM465 NP205 4.10 gears:

Register or Log In To remove these advertisements.