Question about sun tach?

[the duke]

Hello everybody! been a while since i posted. My buddy found an old sun pro tach at the junkyard thats in real good shape and told me to put it in my little S 10 pickup. Its an electric tach and i have no idea where the wires go to does anybody know of any kind of wiring diagrams or could you tell me which color wire goes where? Thanks a bunch! http://www.jalopyjournal.com/ubbthreads/images/graemlins/smile.gif

[TagMan]

Black = Ground
Red = 12V
Green = Negative terminal of coil
White = Light switch

At least that's how my tach is wired.

[the duke]

thanks tagman but now that i have had a chance to look at it all it has is three black wires two bigger wires like ten gauge or somethin and a smaller black one?

[TagMan]

All three wires are black ????? Sounds strange that they wouldn't have color coded them. Maybe somebody rewired it. Can you take off the case or cover that the wires pass through? Maybe we can tell from how it looks inside.