bigbadswingdaddy,
This is my second attempt at a reply...the first made no sense..I hope this one is better.
If you are going to be installing a alternator, then this isn't going to be a restoration...correct!
The wiring harness will still have its wires going to the same physical location, positive or negative ground.
You will make the determination yourself when you connect the 'few' wires that would be polarity sensitive, which way you want to go.
If you are not restoring, a negative ground system would be much easier to deal with.
Your heater fan motor very well might work on negative ground, it depends on how the motor is constructed internally. It would be prudent to install a voltage reducer before a 6 volt fan motor to prolong its life.
If your fan motor will not rotate in the proper direction when polarity is switched, maybe a new 12 volt, negative ground motor would be a thought.
Alternators are available in 6 volt positive ground so they could be available in 12 volt positive ground as well. The burning question would be why stay with the positive ground if not a full blown restoration.
Stuart
