I'm done with the engine swap in my GTA, but the alternator is not charging the battery. It was charging the battery just fine before I swapped the engine My alternator connector has 2 wires on it. With the car running, the thick red wire has 12 volts on it, the other tan/white wire has 0 volts. The wire going to the battery has 12 volts on it too. It should be 14 volts.

What are the red and tan/white wire for and what signals should they be carrying? Where do these wires go? Any ideas on how to get this thing charging?