Aftermarket trip computer for OBD1???

[Vettepilot]

Fixing up/restoring a 1994 GMC K1500.

I absolutely love trip computers for monitoring fuel mileage and averages and other trip info. I know it was done and offered on OBD1 computer systems because my 1987 Vette has it.

I have been searching and searching though, and cannot find a Trip Computer to add to my 1994 OBD1 GMC pickup.

Help anyone???

Thanks,
Vettepilot