In about three nanoseconds there will be half a dozen doomsayers telling you that if you run alternator output through your ammeter there will be a conflagration rivaling the Chicago fire under your dash. Ignore them. Disconnect the "BAT" wire from the regulator and do a very good splice (preferably soldered) to the wire you're planning to use as the alternator output. An 8 gauge wire should be about the right size. Your ammeter and the rest of the elrctrical system will work exactly as it did with the generator. Disconnect and insulate the other two wires at the regulator and the other ends of them at the generator. The "armature" wire at the generator might be a little too light gauge to work well as an alternator output wire.
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!