When putting the center console back in the '74 that was originally in the car years ago I have a problem. When I pull on the light dash switch and move the reostat to adjust brightness in gauge's, my volt meter and temp gauge's go to zero. If reostat is either to far left or far right they work ok. Also adjusting of brightness seems to have the opposite effect on dash then on console, one goes bright and the other gets dim!

One more thing, the dash blinking brake lite does not go out when the car starts, just keeps blinking.
What to do or check? Original wiring has been slightly cut up but not too bad, I have seen worse. I have checked everything out with the factory wiring harness diagram.
Thanks for the help.

The 74s have the center console gauge lights on a different circuit than the dimmer that runs the dash gauge lights. They do not dim.

The black/blue wire for the center console gauge lights should hook up to the grey wire that goes to the engine compartment light and to the license plate lights. This should happen at the plug that is under the center console.

The brake warning light not stopping is likely due to someone bleeding the brakes and then not pressing the reset button on the master cylinder. Remove the gravel guard from under the front of the car, and find the master cylinder. Where the wire(s) plug into it, you should find a rubber nipple. Press on this; the reset button is behind it and will be pressed if you do that. Then check continuity from the brown/white (brown/yellow??) wire to the brown wire (if plugged into the MC switch) or to the MC housing (if the MC switch only has one wire plugged into it). You should now have no continuity.

If the light still won't go off, then check the button under the handbrake handle to make sure it's pressed down. And check to see if there is a wire connected to it.

--DD