That’s a classic worn headlight switch issue. The dimmer for the gauge lights is built into the switch, and over time it gets dirty or worn out. That’s why you have to spin the knob to make the lights come on, and why they stay dim.
You can try pulling the switch and spraying electrical contact cleaner into it, then rotate the knob back and forth a bunch of times. Sometimes that fixes it.
If not, the switch likely needs to be replaced. Also double check that you have 12 volt bulbs in the gauges and that the cluster has good grounds, since both can cause dim lights.
Hope this helps.
