I would like to test the fuel and temp gauges from my '64 before reinstalling them in the dash cluster. I know that the constant voltage regulator provides a pulse that averages out to about 5.5 volts. My questions is, if I apply 5.5 volts directly to the studs on the back of each gauge (temp and fuel), will I be able to see the needles move? Or should I apply 12 volts for an instant to simulate a pulse? BOTTOM LINE: What is the best way to test the temp and fuel gauges outside the car? I have lots of tools, just need advice on technique. Thank you.