I took out the tank and sending unit when I had new pans welded in and the gauge hasnt worked right since. I have checked everything from the output of the sending unit to the ground connections for the sender and the gauge. When I filled up the tank it only indicated a half tank. Now as I drive, the gauge shows more fuel in the tank. I dont know if it is equalizing, going the wrong way or my firebird is producing gas as I drive.

If your car is producing gas as it drives...I want one of those!!

Seriously, I know what a pain in the butt that tank is to pull and put back. And if you can't find an easy solution, it almost sounds like you'd have to drain/drop the tank, pull the sending unit, and test everything on the ground.

Maybe someone else has a better idea?

I have done all that before and it all checked out. The meter readings from the sending unit were correct and I have good continuity from the sending unit to the gauge harness.

How was the float?

Stop feeding your 'bird bean burritos. My guess is the float isn't where it needs to be. But if you're showing more fuel than you actually have, I would say it's a ground or gauge problem.