Jeff, "IF" , and that's a BIG IF, you can pull back the dash, or reach up from the bottom, on top of the head light switch is a small button. You need to push the button DOWN to release the lock on the rod that activates the switch and pull the knob gently while pushing the button. The rod SHOULD come out of the switch. Then undo the collar on the dash, screw the retainer off the switch, and unplug the connector. You should be able to bring the switch out from behind the dash and replace it. ALSO, you might try turning the knob for the lights. It is a rheostat that controls the intensity/brightness of the dash lights. I THINK if you turn it to the right they SHOULD get brighter. There is a notch, so to speak, at the end of the travel that you can feel in the movement that turns on the interior lights while the door is closed. Turning it to the left will lessen the intensity and eventually turn the lights off. LASTLY, that is how my 72 works. Not sure if yours is the same. Hope this helps. A new switch in mine made a huge difference. Age has a way of changing the way things work. I'm sure you will concur .
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