1998 Dodge Caravan dash gauges going off and on

My dash guages occasionally go off all at once. They all go to O like they have been unplugged. If I hit down on the dash with my hand above the guage cluster they usually come back on. I would like to look at the electrics, maybe for a loose connection, but don't know how to get the face of the dash off. The front bezel starts to pry off but then resists too much. I don't want to break anything.
Is this a common electrical failure?
How is it normally fixed?