You don't have to ditch the alternator for a newer one. As stated before, the alt plug on a /4 or /6 will plug directly into the VR. Mine is mounted on the wheelhouse where the battery used to be.
AND
You can wire the engine harness directly into the main harness with a matching 14 pin male plug ... no relay board needed.
AND
While the colors are different on the wires, you can match function at the main body harness. Like I said, the notes are in my office and I can get them Monday.
Images at 11!
Oh, I printed the 911 wiring diagrams off the Bird site and traced function.