[dmjlambert]

I have a 1969 CST/10. With power removed the temperature gauge stays in whatever position it was when the engine was turned off. So usually my gauge is sitting a little left of center, where it was when I shut the truck off. If I come back later when the engine has cooled off, and start the truck or turn the headlights on, the gauge will swing to cold. If the green wire that goes to the sender is shorted to ground, the gauge will peg to hot. If power is removed by turning off the key and headlights, and then the green wire short to ground is removed, the gauge remains pegged on hot. When I start the truck or turn the headlights on, the gauge will move to whatever the current temperature of the engine is.