Question 1: I replaced my light switch in the cab and found a broken yellow wire coming from the plug. What is this wire for?

#2: I am suppose to have fog lights (89" vert), but have yet to find the switch or method of turning them on. The interior was partially gutted so I am looking to return it to stock (ish). I do have several wire ends that are not being used so I assume it has something to do with those.

#3: Tachometer not working. Was working intermittently, but I changed the pod (which it does not work at all) and I have not found a successful pre 90 wiring diagram. Any info appreciated.

 

Not all have fog lights. Mine didn't.
The FAQ has a few older wiring diagrams. Try the online manuals the FAQ lists. www.autozone.com has some.

 

Who would have thought. I found the wiring at the autozone site. Very helpful and cost effective so thanks. Apparently, it is for some interior lights.