Ammeter pegged...
Now I'm going to go back and read this whole thread again.
You and me and everyone else too! LOL
Since it showed roughly 40 amps charging, the regulator must be grounded. If it wasn't, then power could not flow through rotor unless the green wire is shorting.
Look carefully at the green wire from the alternator field terminal to the regulator. If that terminal or wire has poor insulation and can touch ground, that's one possibility.
Another possibility is an internal failure in that P-part regulator.
Last, but not least, is a poor connection with the blue wire at the regulator or where-ever its spliced in. The rest of the blue wire (after the splic)e must be good or the rotor would not have had recieved much if any power.
