Gauge Cluster Lights Not Working

[1981chevy4x4]

My 81 chevy k10 the gauge cluster lights recently stopped working the ones that light up the speedometer and other gauges. The signal light indicators light up when I turn them on and it shows when my headlights or on bright are they on the same fuse/circuit?

the interior light also works when I turn the headlight switch but no gauge lights.

I have heard some people say it could be the headlight switch but since the interior light turns on by it could it still be the headlight switch?

Apparently a lot of people have problems with this so I was hoping someone on here could help.

Thanks in advance for any help.