Ponderosa, Sooooooooo many questions so little time lol lets start with the basics.
1) Most allllllllll alternators including those Delcos require NEGATIVE GROUND PERIOD so I wouldnt try n wire it up at Positive ground whatsoever. i.e. hook the batery up with its - post to frame ground and + to starter/switch BEFORE you install n wire the alternator.
2) The starter will still work fine n turn the same direction REGARDLESS OF POLARITY i.e. if you convert to neg ground to accommodate the alternator NO PROBLEM with the starter.
3) Assuming its the standard points n condensor battery powered coil ignition NOT an electronic ignition (which IS POLARITY SENSITIVE), it will work at EITHER polarity buttttttttttttt the coil works best if its wired to match the polarity i.e. if at Neg ground its + gets voltage from the ignition switch and/or any ballast while its - wires to the distributor. If at Pos ground reverse that with - getting voltage from switch/ballast and + to teh distributor.
4) In the event you need to change from pos to neg ground the ammeter leads need swapped or else it will read bass ackwards. It will work at EITHER polarity but if you change things the leads need reversed.
5) If youre at 12 volts the coil must be a full true 12 volt rated coil or rlse if you use a 6 volt coil it needs an external series voltage dropping (12 to 6) ballast resistor wired in after the switch and before the coil.
6) Many people use the GM 10 SI internaly regulated 3 wire 12 volt alternator wired n configured to work like a one wire unit, post back if you need wiring instructions.
Hope this helps, post back any questions
Ol John T and all in Indiana