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lynnfield · 12-16-2014, 06:49 PM

With all of that this was the most important thing. Follow the wiring diagram completely in that thread and you will have low speed only. I spent a day alone on this. The wiring for the relays is correct, if you look at the orientation of the factory plug (the 3 wire one that plugs into the stock switch) it is backward or upside-down. If you wire this up as I did and have low speed only swap the hi and low speed wires at that plug and all will be well. Also all the Cole Hersee switches with the 75600- part number look to be the same as long as they are 12v. If you get the 75600-02, it comes with a 6 wire packard 56 connector already on it, and you can order the female connector #2977044 and wire directly to it. I found the switches at a local big truck repair shop here in Waco (Truckmotive) for $59.

Relays I used: https://theelectricaldepot.com/index...93964d5ce92511

6 way connector: https://theelectricaldepot.com/index...93964d5ce92511

Use these 3 way connectors to replace the factory plug for the original switch: FEMALE: https://theelectricaldepot.com/index...d709cb2db5040b MALE: https://theelectricaldepot.com/index...d709cb2db5040b

I used these also to hold the relays, the bases lock together: https://theelectricaldepot.com/index...93964d5ce92511

Last thing, order the terminal connectors for the relays if you use those bases: https://theelectricaldepot.com/index...93964d5ce92511

12-16-2014, 06:49 PM	#187
lynnfield The Waco Kid Join Date: Oct 2009 Location: Waco, TX. Posts: 1,781	Re: First Steps LS Swap...... With all of that this was the most important thing. Follow the wiring diagram completely in that thread and you will have low speed only. I spent a day alone on this. The wiring for the relays is correct, if you look at the orientation of the factory plug (the 3 wire one that plugs into the stock switch) it is backward or upside-down. If you wire this up as I did and have low speed only swap the hi and low speed wires at that plug and all will be well. Also all the Cole Hersee switches with the 75600- part number look to be the same as long as they are 12v. If you get the 75600-02, it comes with a 6 wire packard 56 connector already on it, and you can order the female connector #2977044 and wire directly to it. I found the switches at a local big truck repair shop here in Waco (Truckmotive) for $59. Relays I used: https://theelectricaldepot.com/index...93964d5ce92511 6 way connector: https://theelectricaldepot.com/index...93964d5ce92511 Use these 3 way connectors to replace the factory plug for the original switch: FEMALE: https://theelectricaldepot.com/index...d709cb2db5040b MALE: https://theelectricaldepot.com/index...d709cb2db5040b I used these also to hold the relays, the bases lock together: https://theelectricaldepot.com/index...93964d5ce92511 Last thing, order the terminal connectors for the relays if you use those bases: https://theelectricaldepot.com/index...93964d5ce92511 Last edited by lynnfield; 12-17-2014 at 04:50 PM.