Here's the deal.
The specifics of the system are critical in trying to walk someone through the troubleshooting process.
Otherwise we who are trying to help have to give a bunch of IF this then that scenarios.
So I'm not going to do that.
However, you can pretty much figure this out.
The operation of how a grounded field system works (that's the type that your earlier regulator is) is explained here:
Identifying Chrysler Alternators (1960-1976) (you can get more details of the mechanical regulator in the Chrysler Master Tech Conference. A search will turn that up.)
Use a voltmeter with the car's ammeter to figure out IF its a high voltage issue, under what conditions that occurs (slow idle, above idle, or follows rpm). Then you'll know where to look for the cause and solution. With the engine running at those different speeds, observe the ammeter and measure voltage at the battery, the alternator output and the regulator input. That's it in a nutshell.