Here is the situation. Headlights, taillights, blinkers all operational. When adjusting dash lights the guages all read about a 20% indication. When rheostat is adjusted so no dash lights, guages work. Also rheostat adjustment also causes dash turn indicator lights to illuminate.

Any ideas?

 

Sounds like you got some bare wires touching. You need to locate them. Happy hunting.

 

You have a broken printed circuit trace on the back of your cluster. Same thing happened to mine several years ago..lights off, all worked fine; lights on and the right turn indicator came and stayed on, the oil pressure guage would top-end, and the tach would just 'float'.
Pull the cluster out and carefully check the traces (copper lines) for any broken ones; mine had one where one of the bulb sockets went in. I 'jumped' the broken section with a short length of light guage wire, and have had no problems since.
Hope this helps

Pete

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