Funky alternator wiring- '73 Duster

I don’t know why you just cut the taped harness back and chase the wire to where it goes.
Or put a meter on it and ohm out where it goes.
Charge would go back to battry.
Somone may have found it necessary to ground the alternator.

These cars are old, each owner over the years had their opportunity to dick it up.

If charging system works, cut the harness tape back and rip it out.
and tape it back up.