I know its been covered and I've searched but cant seem to fix this issue. I went from a 2.8 to a carbed 350 (no ECM). The original 2.8 wire harness has 3 wires, red, tan/white, and black. Then the big black/red to the battery.
I wired the big black/red and the red to the post on the back of the alt. I ran the tan/white to a 12V ign feed. I cant find a black wire anywhere in the diagrams. I have a gauge, not a bulb in the cluster. It's a Delco Remy alt from ( I was told) an 86 V8 car. The alt has 4 pins in the connector plus the post. Any ideas what I'm missing here? Oh, I had the alt tested and it tested out good, so that's ruled out.

 

Found my issue, actually a couple issues in one. The "black" wire is the brown one in the diagrams. When compared to a black, it looks brown, when compared to brown (not tan) it looks black lol. Anyway, that one needed a resistor put in line for it and now everything works.