Joe, is this on your 68?
If so, here's what the shop manual has for it...with the alternator in the car (for orientation purposes, and looking down at the back), the are 4 posts. The one at the very bottom doesn't get used. Again, looking at the back and going clockwise from the post closest to the head, you have a black wire, and unlabled wire, and a black w/yellow stripe. Hmpf, that doesn't help me very much and I'm looking at it.
Here's what I see with the same perspective at my own 68's alternator, again, its in the car, looking at the back, clockwise from the head there is white thin wire w/black (maybe blue) stripe, then a heavy black wire, and then a solid thin white wire. The very bottom post is unused.
My wiring harness is a reproduction and I have a tach, so not sure if it matches up with yours.
What else are you looking for?