This isn't done, the A/C is not done, obviously and I am not positive how the wiring will get finished. And this is my '72 C10, so not the exact situation as yours.
It has electric choke on the carb, lock-up for the 700R4, temperature gauge wire, alternator wiring and charge wire, distributor power and tach wire tucked out of sight without getting too crazy about it. The circuit breaker on the right fender feeds and auxiliary fuse panel under the glove box area. And a remote solenoid for the starter. It had less stuff visible when it was HEI, but I installed an MSD, so the remote coil got in there.
These trucks originally had a wiring "gutter " at the top of the firewall with wires just dropping down from there onto the engine. We ran most everything into the left fender, and then forward and down. Everything is in split loom as I wasn't trying for show level.
@500$k5 was the main man on this project, and we were just trying to see what we could do! It came out great in my opinion! But I don't have the desire to hide the plug wires underneath like the factory did, so they stayed as pictured.
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