As HCB has said
THIS is the correct sender if you have stock gauges.
Buy that, Put in on/wire per original method and try it. No testing with meters or wires touching this and that or heat guns or wrapping wires around sender turret.... start the motor and observe where pointer is and what it does after warm up. Then report exactly what the pointer does before doing anything.
We do not need a discussion about thermostats or anything else. With 3 dots, this is an approximation gauge.
These are the alleged specs:
220 degrees 88-72 ohms
Alledged specs are all over the place, you don't care what they are if you buy/have stock 59 gauge and stock sender and wire it correctly and don't burn out one by "testing". When we hear what the result of a new set/CONFIRMED correct set, we will advise next steps. One step at a time. So if you are at a point where you need help, wait for responses AND questions for you.
FYI: Aluminum is one of the best conductors known to man.
The brass neck on sender is not supposed to be grounded with a wire.
Use Permatex High Temp Thread Sealant.
