Buy an alternator today before you go on a 8 page study of ancient electrical philosophy and endless tests of all those wires, the voltage regulator, the generator, battery chemistry, idle speed, polarizing, near death if you get an alternator, belt tension, brushes, contacts, coils, relays.............
One thing you won't hear is anything negative about a alternator. Nothing. Silence.
Delco 10si, $50, to your door in three days, two wires, throw everything else in the dumpster. done. ALL trouble gone.
3,,,2,,,1,,