Volts really high with acceleration.

Mr.Plater
Oh dear, I missed that it was a 68.I screwed up.
Bill and Robert and everybody else are right. Unless you have converted to an isolated field system from 1970 or later; which I highly recommend for nearly trouble-free motoring.This is an easy retrofit.
I stopped using that Electro-mechanical regulator,nearly 4 decades ago. When it sticks at night, it tends to fry stuff,starting with headlights,and as soon as those go it's lights out everywhere. And then the power has no place left to go but into the ignition system and battery. And the bulkhead connector is also an early victim.
And there you will sit on the side of the highway, on a dark night, with your arm in the wind, and your thumb pointed at the stars, hoping someone will have pity on you, and offer you a ride, or a phone,lol.Pray it doesn't happen in winter.......... Or maybe that stuff just happens to me, with a howling wind,and at an hour with no traffic.:(