How do you change the fuel sending unit on a 1981 CJ7 jeep?

To change the fuel sending unit on a 1981 Jeep CJ7, first, disconnect the battery and drain the fuel tank. Remove the fuel tank by unbolting it and disconnecting the fuel lines and electrical connectors. Once the tank is out, take off the sending unit by removing the retaining ring and lifting it out of the tank. Replace it with the new unit, reassemble the tank, and reconnect everything.