I am looking for an aftermarket tach that would be compatiable with DIS on my '95 88. I have located several OEM insturement panels with the factory tach in in but in looking at my FSM, the panel wiring harness is different with the optional tach.

Thread moved to Oldsmobile section.

the harness itself?

I got lucky enough to find a wiring diagram for my display on my Turbo Grand Prix. There is a white wire that you can use for the tach signal. Pm RobertISaar and see if he can get you a diagram for your car.

yeah, generally there will be a white wire coming off of the ICM, that'* a 1X square wave signal used to drive the tach.