I'll have to check the wiring diagrams. That tach was used from 66-69. The 66 models used the sending unit, 67-69 did not. I've also got a very nice one that I pulled from a 67 Dart GT many years ago, but I think the box it's in is buried in the spare room so I can't just look at those wires.
Same as Jim said, except, I do have 2 console tachs the 1966 tach that needs a seperate sending unit that is in a round tin can and my other one that is mounted to my console has the sending unit inside the tach itself. I do believe that 67-69 have 3 as shown black, green, and orange. as I was looking at the pic it may have a purple wire also. I do know the 66's have a yellow wire.