kschilling,

Are there solder marks on the wire that look like those on the condenser? If they look alike, you've probably found the connection.

You could start the car, touch the wire to the end of the condenser and see if the TACH works.

bg489,

I think you have it backwards. If you look closely in the picture, you can see the words TACH on the left and BAT on the right. Right above that are (from left to right) C- GRD B+

In any case, he's not looking for where to attach to the distributor, he's trying to find out where to attach it to the signal lead that goes to the tach inside the car.