I looking for some information. I have 1974 gremlin 6 cly Just purchased a dash cluster with a tach . Is there a special harness that I need to hook it up. I took a wire from the tach side of the dist. hooked that to the neg side of the tach and the pos. side to batt. and it stalled the engine not sure theres a special harness or the tach is shorted Thank you Tom Tente