another interchange question wiring this time.

[original balzer]

My 77 has a hamfisted previous owner clusterfock in the light wiring. It was rigged up to have the head lights on any time the key is on.

Anyway the plug and harness for the light switch was all cut out and replaced with all blue wires. The problem is I CANNOT for the life of me get the tail lights to work I have had it bypassed a few times but doing that gets the wire hot.

I have a 83 diesel and it has blade fuses witch would also be a sweet upgrade from the glass fuses.

So can I just do the in cab part does the harnesses come appart at the firewall so that I can just leave the chassis wiring? or would I have to swap out ALL the wiring bumper to bumper?

 

[79rustyk10]

When I did the TBI swap in my 79, I put the entire fuse block and underdash harness from an 88 K5 parts truck into the 79. I had to switch the plug for the headlight harness, as the 88 K5 has 4 healights while my 79 obviosly only has 2 headlights, but the plug for the taillight harness(79) plugged right into the fuseblock(88). I dont know but a diesel harness might be slightly different but I dont know why it wouldnt work.