Ed, that was one of the Delco Remy part numbers. RBM had another number for the same part. They were interchangeable.

I'm unsure of what solenoid I will need now that I am converting to 12 volt. Could someone tell me the number?

anyone?

Ideally a '48-'49 solenoid, since the pull-in and hold-in coils are separate, each with it's own terminal. Let's you put a resistor in the hold-in coil circuit, which is energized whenever you're above cut-in speed.

For the pull-in coil there's not much of a problem, as it's energized so briefly . . . I suggest powering it with a 16 ga. wire, which will act as somewhat of a resistor.