I believe I've heard that people have looked before, has anyone ever found a schematic for these dashes?

Randman and I both have the exact same problem. Dash works great except oil, water and boost gauges have their own minds. Mine changes with the temperature. Sounds like a cold solder joint, but I couldn't find any (and I work on arcade games...I'm used to looking and finding them)

Sort of sounds like a capacitor or resistor breaking down. I'd be interested to look at the schematic and find the grounding or main power to the gauges. This is a simple fix...but need to find schematic to see where things are. Have a feeling it'* on the little board for those three gauges. Anyone tried to swap it out and have success?