my 72 has a charging problem that i don't understand. when i let the car idle i got 12.06 volts coming from my battery and the gen light is on. when i had my friend give it some gas the voltage dropped to 12.04 but the gen light went off. this is typical of the problem and alwalys happens. The only thing i have done so far is check to see that my alternator belt is tight on my new alternator and checked my grounds.