Squareback vs round back alternator?

Yes the transistorized version of the voltage regulator that looks like the mechanical regulator should work with that alternator and alternator wiring.

If I recall correctly 1960 may have used a starter with a remote starter solenoid.

I'll have to try to enlarge the shop manual photos and your drawings. They look great. Just hard to read because the forum softwaree shrunk them. If you can turn them horizontal before loading to the forum, they won't get shrunk as much by the forum softeware. I'll spend some time looking over your phtos and information this evening.