Problem with gauge lights.

I have a ''97 LT, 4D, 2WD.  And 2 weeks ago my brother was driving it and the gauge lights (All but the emergancy lights, brake lights and warning lights), went out at once. The gauges still work fine, as do the lights throughout the rest of the truck. We''ve checked the fuses, and even popped the gauge pod out and checked the gauge bulbs, none of which seemed to be burn''t out.

Any help would be much appreciated.