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Me again, My fuel gauge reads passed the full line. When I turn it off it goes back down. Its been staying at that spot for the past 3 days. Not sure if it's a bad sending unit or faulty wiring. I haven't had a problem before. As soon as I turn the car back on it shoots up to full again.

Probably a bad sending unit or the wire between the unit and the gauge has found a ground.

Believe you have a 48 so the sending unit is not a pure resistance type. It is bimetal which has a heater working a bimetal strip in the sending unit. The output is an on or off type operation. Fuel level changes pressure on the bimetal resulting in longer or shorter periods between the on/off cycles. The gauge responds by its heater moving a bimetal connected to the needle when on and stopping when off. That makes it hard to troubleshoot. You do not want to leave the gauge pegged or it could burn out.

It is most likely that the sender is the issue but the wire for the sender goes thru a small hole in the trunk floor at the extreme rear near the latch striker. Then continues over the top of tank to the sender. The hole should have a grommet to protect the wire from floor sheetmetal but it could have deteriorated letting the wire short as it goes thru the hole. Check that spot and also the route above the tank where shifting might have pinched it. Otherwise the wire goes overhead above the headliner along with the tail light wires. That length is not too susceptible to damage until it drops out of the left windshield pillar and goes on to gauge. If wire is still the old fabric type a chunk of insulation could have fallen off in that stretch and wire could have touched metal.

Also,a heavy load in the middle of the trunk can cause the floor sheet metal to contact the terminal on the sending unit and ground it out.
There should be a rubber boot covering the connection but it may have deteriorated over time.

You guys are awesome... I followed my wiring down to the tank, seemed fine but replaced it anyway. It didn't fix the gauge, however, I did just recently move my tool box and extras to the middle of my trunk. Pulled them out turned the key and presto! It's fixed! I applied some weight by hand, seems some metal work is in order here 😞 Thanks guys!

Slip a thin sheet of rubber between the sensor and the trunk floor pan unless you want to drop the tank and do something more elegant.