LATE ANSWER TO OLD QUESTION

I guess a late answer is better than none at all.

We had to replace one new voltage regulator during the ’48 restoration and being the pack rat am, I kept the “new bad one”. In the bottom of the box that had the bad voltage regulator in it was a set of installation instructions that included how to polarize the regulator.

Disconnect the negative battery terminal
Remove wires from terminals noting location of each one
Remove old regulator
Install new regulator
Reattach wires to same terminals as original unit
Reconnect negative battery cable

Polarize Regulator

Obtain an 8-inch piece of 16-gauge or larger jumper wire
Momentarily (no more than 2-econds) touch the jumper wire to both the armature (ARM) terminal and the battery (BAT) terminal. There may be a brief spark, this is normal.
CAUTION: Do not touch the jumper wire to the field terminal (FLD) or ground
Start vehicle and check for proper charging system operation.

I still believe that since the regulators have been in service already, they won’t need to be re-polarized – even after boo-coo years