Round back alternator
I grounded one of fields to the case. I have a 65 Barracuda vr electronic upgrade , done the bypass volt , cracked back’s headlight upgrade with bigger wire from alt.,electronic dist. Mopar , had another round back 60 amp in there first trying to figure out why it was doing this checked everything and regrounded everything was new except dist. Finally took the first alt. To get checked while being checked it was in full field then nothing, got this one same thing I might be the lucky one finding bad refurbished alt. The square back is original 76 year that was upgraded to 90 amp 25 years ago I did. System is still one wire