I may have anticipated Firstowner chiming in.
My responses in blue.
#3- My truck has a black rubber coated version to retain the front harness to the firewall between the engine side of the fuse block and where the harness passes between the inner and outer fenders.
Understood. What steered me from that is it's Chevy engine orange and no rubber.
#4- back of alternator.
Ah, confirmation thank you.
#7- Used to retain the positive battery cable to the lip of the oil pan as it passes to the starter.
Heck yeah they are. Sure a better fit than my suggestion of a/c & blower wires, which probably wouldn't work. Still #1 is a mystery.
#10- Can't tell for sure but that type in various sizes is used to hold the parking brake cable to the inner fender, the fuel line to the frame (in at least one place), etc.
These aren't for the E-brake on either of my trucks. See post 5 if interested. One way or another I'll find use for them.
#s 8, 9 11- possibly for wires. For example, one something like #11 is used at the side of the water pump on my 350 to retain the wire that runs to the temperature sensor that is mounted in the left head. That wire is encased inside a fabric loom.
I see my 72 has the fabric loom. Must have been removed from the 71, and I believe we installed the sensor on the wrong head (right) with the rebuild in 93. That said, from this angle the routing for that wire is "peculiar". Runs with the rest of the wires through the F/W gutter, back over the rear of the block to the LH head.
The transmission lines are not secured to the engine or frame in any manner. I don't believe that would be a good idea as they would be twisted/flexed every time the engine "rocks" under acceleration. The clip on the lines only holds the lines together as they run from the transmission to the radiator.
I recognize that clip. I still have mystery clip #1, but I get your meaning. I'll add your clip to my wish list. For what it's worth, my lines are bound fairly tightly to the motor mount perch using a clip on my 72, using a clip similar or exactly like #5. Nothing on the 71.
The top picture (front of engine to the right) shows the positive cable clips and a transmission line clip installed.
Clean undercarriage.
The second and third pictures show the positive cable clips, an additional clip and my notes regarding placement of those clips.
I recognize said additional clip. Mounts to the "lip" on top of the frame.
The fourth picture shows the front harness clip and the clip on the parking brake cable. In the fourth picture you can see another similar "J" clip holding a red 12 gauge wire. That wire is the hot positive that is part of the camper wiring option. That particular clip is upside down and, if I remember correctly, has been since the truck was new.
No reason to change now.
On a side, concerning the pipe clamps per #6. I suspect they were used for the aux. transmission cooler or saddle tanks on this truck. I remember seeing them on to far to remember, just not where. It's not as if there are many options, considering they fasten using a #10 screw.
Thanks a bunch Jim. Appreciate your time & info.