Flickering or pulstating Headlights

To add to the confusion, in 1976 Chrysler made 4 alternators that looked the same [square back]. 41 to 65 amps. They also made a 100 amp that looked different [no fins].

They also made 2 different size pulleys [~2 1/2'' and ~3'' diameter].

The full field draw for the square backs is about 5 amps. The full field draw for the old style is 3 amps.

I think the flickering is due to the regulator going from full field to a lesser current and back again. In the past, I'd drive around with the lights on to lessen the flickering.