choosing the right alternator

Let’s dust this off shall we? I have a silly question or two...

Using the 1 wire as we know eliminates all of the external charge stuff. That said, can I eliminate the harness from the bulkhead connector that is for all of the external stuff. ie: ballast, voltage regulator, etc? I can’t see where that harness powers anything else. Enlighten me please.

Also, same with the wiper motor harness, correct? I have no wiper motor.

Someone above said the 1 wire will
“reduce” the function of the ammeter. Wouldn’t it be eliminated and thus no need to do the bypass trick?

Thank you from a OE wiring challenged guy!