Instrument panel lights

I have problems with the lights on the instrument panel and all other lights that use the dinner switch. Car is imperial 1969. I get No current to the fuse ( current goes to the dimmer switch to the fuse and then to lights)

The dimmer switch also turn on the dome lights when on max light. That dont work either.

The switch seems very hard to locate. Looks like a pain in the as to remove and replace/check

What to do?