Well to update; my Charger Specialties tach is apparently NFG. they used some sort of composite/graphite body when I bought mine and there are grounding issues. I bought the tach probably 8 years ago but the car has less than 20 miles on it...didn't last long!

Sooooo, I can rip it out, take it apart and attempt to add proper ground wires.....or I can buy a new one somewhere and replace it......or I can give up and bolt a tach to the steering column like people used to do back in 1969.


Dave