2004 Chev Cav Cluster Panel Issue

I have a 2004 Chev Cav that has gone crazy! It has approx. 55k miles on it right now.
Each gage in the dashboard cluster moves in whatever direction it wants. First the temp gage began to move in a clockwise direction and I thought the engine was overheating - but it wasn't. Then the tach gage just stopped working altogether. Then the fuel gage moved clockwise to the bottom of the gage and pretty much stays there moving back and forth across the bottom of the gage depending on the fuel. Now, my speedometer gets stuck when the temp gage gets in its way and while it reads 100 miles per hour, I know I am only going approx. 65 - 70 mph.
Right now the only thing that is working properly is the "check gages" light when I am low on fuel - thankfully. What should I do?