Pishta- thanks. This was a full off restoration of the body and everything was removed for 3 years rebuilding. I was looking at the FSM for wiring schematics and found a few issues with the schematics. I went to the formula S car I also have and found the tach sender had a harness but I could not get into the car enough to see if the sender on the bottom of the left “A” pillar door support and of the tach harness had a wire all ready into the passenger compartment for (-) coil pickup. This car has the aftermarket 66’ tach I’m using with the fuel injection. I did not want to modify harness or harness plug if wire was already there. Joe