There is a voltage regulator built into the fuel gauge of the rally dash. It's job it to reduce the voltage from 12 to approx 5 volts to power your gauges. There is a set of points in there that are controlled by a bi metal strip. If it fails closed, gauges get 12 volts and get cooked. If it fails open, the gauges won't work. Your gauges may be fine if you got the power removed quick enough.
Most folks defeat the regulator in the gas gauge, and replace it with an external solid state unit. There is a member building them here on the forum.
If you cooked yours, I have some spares. Keep me in mind......(the solid state IVR is the little box on the left with the 2 wires...12v in, 5v out)
BTW.......Sounds like you need to start doing your own work. With these old girls, the learning curve is not that steep.....And plenty of good folks here to help you along the way.
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