The gray wire in main dash harness is power for the clock only. You need a separate harness for the tach as suggested above. The gray wire in the lighting harness is for hood mounted turn signals.

Last edited by 70gtx440dana; 12/05/21 03:17 PM.
70 Road Runner 383-4 4 speed FJ5 & black guts
70 Charger R/T 440-4 4 speed FJ5 & white guts