Dont even get me started about freakin lights
My money is on the switch, I have the same problem right now, the compass light will come on, but the lights only work "sometimes", which has turned into hardly ever. Might be a voltage issue with the switch, shorter wires to the gages?
Check the contacts on the bulb, I had a problem with corroded contacts, replaced the bow light and worked until the switch went.
Check any in-line splices or like likwid said look for knicks.
Get a voltage meter and check the swithc contacts first, then check the light contacts. It s a real PIA to figure out without the meter