No Chrome Alternator for me either.

I was wrong. '64 cuda was correct that some electronic regulators could not handle the current draw of later alternators, per slantsixdan. However, not because of alternator output current, but rather from the higher current draw of the field (>3A). However, there is probably one-to-one mapping, so a rule like >70A output alternator will kill an early electronic regulator probably works.

Re knowing your alternator's output rating, I am going out on a limb, but think the early round frame ones were all <45A, unless they had a J.C. Whitney upgrade kit (how could you know?). The later square-back ones (ca 1980's) were ~70A I recall. slantsixdan's suggestion to get the later electronic regulator should work for any alternator.