I rewired my car, as some of you probably know after the 5,000 posts I placed up here. My next problem is I don't know which wires from my 4 wire (Green, Black, White, Red, I think) aftermarket tach go to which wires in the wiring harness. Any help?

Diagrams are ALWAYS appreciated.

What brand Tach is it? Red is almost always a positive connection. Typically from a fused source in the fuse box. To power the light inside.

Is it possible to look closely at the back where the wires are located to see if there are any ID's on where each wires go.

I have a Sun Super Tach II that has all the wires the same color for some reason. The wires are not painted in any way, they are actually the same color and it looks like it has never been apart to fix anything. The ground wire is commonly black.

Typically, the wiring is:

Black wire to a ground source

Red wire to any vehicle harness wire or fuse panel connection which is energized with battery voltage only when the ignition key is in the on position, not to the accessories position.

White wire to the instrument panel lighting circuit or any lead that is controlled by the instrument panel dimmer control.

Green wire to the negative(-) side of the ignition coil or to the TACH terminal on an HEI distributor cap.

Thanks