You don’t have your plug on the alternator installed backwards do you? That will cause the alternator to go to full output. As for the alternator swap, I didn’t run a 1 wire, I used an internally regulated 10si. It’s as easy as cutting the old voltage regulator plug off, and splicing the 4 wires that remain together. Like this:
http://67-72chevytrucks.com/vboard/s...d.php?t=362957
The benefit of using the later alternator other than internally regulated is you also get more charging amps.