Alright after a few months of working on my hack job 72 cutlass w/ a 455 that was overheating, having my new aluminum ( thankfully cheapo off of ebay) radiator stolen out of my backyard (probably sold for crack) I got a new radiator, shroud, and belts installed. I ran new trans cooling lines and replaced the horribly wrong upper rad support that tilted the rad about 20 degrees toward the engine. ANYWAY started it up, now my temp sending unit isnt working. It was yet another hack job hookup, it seems to be just a wire stuck into the top of the switch. The car has an aftermarket sunpro temp gauge in it, so I guess since it is a wire and not a cap. tube, it is electrical and not mechanical. See I'm smart. In any case I am looking to replace the switch, and don't kniow where to start. I have looked through Paddock, Fusick, etc, and have found the spade terminal type, and the "mushroom top" type. I know the spade, but what kind of terminal connection do I need for the more common mushroom? Also are the aftermarket switch sold at local parts stores " uncalibrated and inaccurate on vintage cars" like a few websites I looked at claimed? Any advice would be nice, cause I just want to drive this damn thing!!

 

The mushroom style sender uses the same Packard 56 series connector as the other factory spade terminals on the car. The single terminal plastic connector has a U-shaped notch in the side so the connector slips over the mushroom post from the side. In other words, the connector is aligned at 90 degrees to the centerline of the sender. These connectors are very common on 80s vintage GM pickups.