Dash lights are a bit of a trick.
There are two power sources to the headlight switch
One comes off the ammeter and is NOT fused, only for headlights
The second comes off the tail fuse and provides tail/park and dash light power.
That power goes through the switch, and through the dimmer control, and out on a brown or tan wire, and runs down to the "inst" fuse on one end of the fuse panel.
Through that fuse and then out to all dimmer controlled dash lights on orange wiring.
So with the tail/ park working, wiggle the 'eck out of the dimmer control, and look for any activity, radio, heater, or cluster. Turn the control "towards the left."
Then access the fuse panel and check for voltage on both ends of the inst fuse.