I have been messing with this when I have time. Gauge does not do anything. I did the in dash wire swap while doing an engine swap. It is an 85 4 speed that now has a 2.8 (originally auto) from an 87. I have tried 3 temp senders, and when I ground the wire to the block I get the needle jump and the light. I am going to try some resistors this weekend. After reading a bunch of threads I remember someone saying that only ac delco senders would work properly. Mine is a motorcraft. I was wondering if this is true? My local autozone can't get the ac delco. thanks.

There should be 2 wires....got the right sensor?

Yep. got the one on the right. For a long time I had the other one in there. Parts store sold me the wrong one. The one in there now has the blade type pins and has nothing on the threads that might block it from grounding. I have acquired a few resistors to try tonight. I was just curious about what I remembered reading about the sensor. I have tried 2 or 3 sensors and another gauge from the 87 model. It could be just bad parts I guess. I am leaning toward a bad gauge right now. Will try some resistors on it this weekend. It just seems like I saw somewhere that ac delco was the only sender that would work. I will know more tomorrow after testing.

What are you going to do with the resistors?

I plan on using them in place of the sender and see if the gauge does anything. Right now it sits on zero unless I ground the wire, then it pegs so i want to try and find out if i have a working gauge. I would say the wires are good since I can peg the gauge and get the light when I ground the wire to the block. I need to try to rule out gauges i guess.