Use a short jumper wire and connect the BAT terminal of the regulator to the ARM terminal momentarily, like 1/2 second or so. There will be a pretty healthy arc- - -that's normal, nothing to worry about. There is no need to disconnect any wiring, just run a surge of current through the armature to ground to establish "residual magnetism" in the generator of the right polarity.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!