New Van - Gauge Cluster Lights not working

Hey guys, I'm new to the vintage van life but I'm excited to become a part of it.  I recently bought a 1967 GMC Handybus Custom.  I'm working through the minor bugs right now before I tackle some of the more major ones.  Right now I'm stumped by the gauge cluster lights.  They don't come on with the headlights.  I've replaced both bulbs and I believe I replaced the fuse even though the old one checked good.  Where should I go from here? Any help would be appreciated.  As far as I can tell all the wiring behind the dash is original and hasn't been monkeyed with.

Thanks,
Ron

is the fuse the one in the lower right hand corner,,,,,,,,do you have the dash lights turned off with dimmer section on the headlight knob,,,,,,,or the dimmer contacts could be corroded on the headlight switch,,,,,

Yes, I replaced the fuse in the lower right. I believe it was good but I changed it for good measure. With the lights turned on I've turned the knob fully to the right and left with no results. I have not disassembled the switch to see if the dimmer contacts are corroded. That is my next place to go unless someone has a better idea. Thanks for the suggestions.

Actually, never mind guys. I just checked the gauge lights and they are working now. I think it was just the bulbs and I couldn't tell until after dark that they were coming on. Thanks for the help.