Make sure you check the alternator, your posting says that it only has an "hour run time" on it and the regulator is a "month old". Did they give you a replacement alternator with a built in regulator? You state you have an alternator and a regulator. Does the replacement look exactly like the old one? Or did they give you an "upgraded" alternator for someone doing a V8 conversation with a built in regulator therefore you have 2 regulators in the system fighting each other. Just something I noticed that stuck out at me.

Might be nothing, I just saw the first alternator that pops up at the Rock Auto website is the replacement with a built in regulator.

John