Gas gauge not working

I have a ‘74 Duster with a 318. When I bought it, it had a new gas tank sending unit. Before I started messing with it, the gauge would stay showing empty no matter how much fuel I put in the tank. I cleaned and reinstalled the ground strap, and it didn’t make a difference. I ran a hot wire to the tank and it pegged the gauge past full. That might have been a bad idea, as the gauge is showing below empty now.

Do I burn up the gauge by doing this?
Probably so, yeah. All you had to do was GROUND the wire going TO the sending unit. If the gauge is good, it will go to full. So shootin 12V to it probably did it in.