[big gear head]

I bought the terminals that are used in the bulkhead connections and ran extra wires along with the original wires right through the bulkhead. It looks like all of the wires are original to the car.

I mounted my tach in the same place that you are holding yours, but I used a reproduction Nova dash pad in my car, so I didn't mind putting holes in it. I would have a hard time putting holes in that dash pad that you have.