The wires I'm pointing to all go to the external regulator harness and/or back of the original alternator and 99% sure they are all factory. After looking again, I do see a second heavier yellow wire also attached there to the B+ side of the starter relay, so that might be what is actually...
I am not a wiring expert and have been researching replacing the old externally regulated alternator with an internal one-wire alternator. I have a powermaster 1-wire alternator.
When you read everything online for this, most say just remove the old external regulator and then run a heavy gauge...
