I’m in the middle of putting a t2 motor in my ‘86 base NA car and am going to run a side mount alternator. For the most part I don’t need any of the plugs on the main engine harness for this setup since i’m running it carbed and NA. I know where the terminal is for the power wire(ring terminal) but am not sure on which plug in the other harness is for the backside of the alternator. there’s a few plugs on the harness that would fit and can’t quite remember where it was at in the stock setup. This is only a temporary setup for this since i’ll rewire the car later on and get rid of all this excess wiring just want to get the car started and running before doing something more drastic like that.

 

If you've kept the S4 alternator, t's a 2-pin female Yazaki CN(A) connector (translucent white) that comes from the EM harness, or the spaghetti of wires that comes from the passenger's side of the firewall. If I remember correctly, that connector branches off near the ECU temperature sensor, which sticks out of the back of the water pump housing and mates to a green Bosch Jetronic connector with an offset tab. The wire colors you're looking for are white with black striping and black with white striping.





(image nicked from here: https://www.rx7club.com/old-school-o...or-alt-576984/. Splice weirdness is for retrofitting it to an older car)