Hi y'all!
i'm almost done (fingers crossed) with reassembly of my pickup after a complete rebuild of the engine and transmission. Bought it cheap from a guy who got overly ambitious and pulled everything out of the truck without the skills or knowledge to fix it.

So now it's about 95% done, but there are a few little lingering pieces I can't find homes for, and I'm hoping y'all can help. First up is wiring.

I have 4 plugs/terminals off the main wiring harness which I can't find homes for-- see attached picture. They're in order back-to-front of bay along the harness.

1: ring terminal with three brown or red wires, 16ga
2: female blade plug with 18ga yellow/green(? faded) wire
3: 2 prong plug (same shape as transmission reverse)
4: weird round boy, near butterfly valve

 

#1 is the ground strap that goes to one of the bolts that secures the surge tank to the intake manifold.
#2 looks sorta likes like the connector that plugs into the sender unit for the coolant temp gauge. Different color than my 1987, but in the right place.

The other connectors are not similar to mine, so would need more information about the vehicle, like the model #, to figure out. 1991 22RE just doesn't do much in that regard.