Defunct Fuel Gauge

Ever since we had a battery problem a month ago. the fuel gauge no longer works. Ended up having to replace the battery and alternator at that time. Any thoughts as to what could have happened or how to fix / reset to get it working again? :uhoh:

Fuse? Sending unit?

This reminds me of the time i installed a battery on a 97 Malibu. (i work at a shop). I put the battery in, and when the connection made contact multiple times (not getting it in all the way.), it made the guages jump, and then freeze into postion. IT was reading a full tank of gas, with the battery disconnected. weird. So i put the battery in, and it made the guages jump again. Now normally, this wouldnt be a problem, BUT on this specific malibu, there was no peg just past the Full mark on the gas guage. guese what happened next, yup it fell all the way down, and never came above the peg on the bottom. just tries to go thru it.