I did extensive searching but couldnt find an immediate answer. I have in my 88 IROC a 145mph gage cluster (not sure what it came out of). I recently swapped motors and wiring harnesses. Motor is a GM ZZ383, Donor harness out of an 85. I have a white wire coming off the side of the distributor that I am assuming is for the tach and is hot when the car is running. However on the harness "plug" on the firewall the only wire that is available is a brown one coming off the plug.
Questions are: If I experiment with that possible connection (white/brown) can I damage anything if its not correct?
If it is not correct, can I just run that white wire straight to the tach? Thank You