[FWDLK] alternator conversion for 58 Chrysler

Am trying to finish my 58 New Yorker wagon, but there is always something that prevents me from using the car. It has got new italian plates, fresh insurance, new paint and chrome, but can't drive !
Now it's the alternator. During the years, the former german owner has switched to a european alternator, and everything was ok. Now, after car has gone to body shop, nothing is working anymore. So my mechanic has installed a external regulator alternator he had on hand (Mopar origin) with a matching regulator, but he can't get the connections to work ok. The alternator has two posts, one is marked Field, and the regulator has four posts, plus one on the side that is connected to one on the front. The posts are marked Field, and 1, 2, 3. Any ideas on a connection between the two? The old set up used a relay connected,to the regulator, plus some very lousy wiring that my genius mechanic cut off and threw away.