I was suspicious of the temperature gage in my '57. I had to repair the gage when I first bought the truck, one of the rivets that hold the gage face had pulled out and broke one of the hair-fine wires. I made the repair but wondered about the accuracy. Recently I added a triple gage set of temp, oil pressure, volts under the dash, to help with easing my suspicions about all of the gages. The original gage in the instrument panel never registered above 1/3rd although it did seem to work with changing temp. Now with the AutoMeter triple gages I saw that the engine was not getting up to 180 degrees, I replaced the thermostat with another new 180 and both temperature gages are in agreement. My 283 also has the sensor threaded into the intake manifold. I thought I would tell my story just to give you more info, I think I would make sure the current thermostat is holding at 180 and also try a different sender.
