I am upgrading my 81 Nautique that has 1 35 amp alternator with ext regulator with a mondo 55 amp alternator with internal regulator. I got it from DIM with the new wiring harness. I have never done this before and I really don't want to fry this system. DIM said that the post at 2:00 is the output and the ext is the excite, which I figured. The question I have is the ground. DIM said it was at 4:00, but as you can see there are two posts at 4:00. I figured it was the one closer to the middle of the alternator, but wasn't sure since it has a bar running from it to the output post.
Any help with this or general information regarding the rewire since I am going from internal regulator to external regulator would be greatly appreciate. I matched up the new wiring harness and most of the wires are the same with the exception of the purple and the ones running to the neutral safety switch. (The new harness has three wires and the old one only has one wire)