Thanks for the work you guys are doing on this, I really appreciate it. Bear with me as I'm not very good with wiring at all just yet, but is this switch somehow wired in series with my ignition key wiring? I just know I phrased something wrong there... I'm a newbie to this standard trans stuff but I'm keen to learn

 

Yes, for an '85 it should be wired in series with the ignition switch. Both would carry the low-current signal to the starter solenoid to cause it to pull in and start the vehicle. But, like the old Christmas tree lights, if one fails nothing happens.

 

Ok, to qualify this, all this is from my '85 F250.
I did a c6 to zf5 swap, and ran across this.
Under the dash, next to the kick panel, is a 2 wire connector, that with the auto tranny has a jumper installed. On a manual tranny, the jumper is removed, and the connector is plugged into the clutch switch.
You say you have a clutch switch from a truck with cruise, so the switch will have 2 sets of connection plugs. IIRC, one should be normally closed, and one normally open. The normally closed one is for the cruise, and the normally open is for the start circuit.
Just going by memory, it's 4:15 in the morning, so it's dark out, and I can't seem to find my '85 wiring diagram right now. Hope this helps.

 

Awesome, thanks alot! I found the connecter stuffed in behind the kick panel. Be damned if I can get the thing plugged into the switch. I'll tackle it later when I have a little more patience. Thanks again everyone for your help!