For in-tank fuel pumps, first, siphon any remaining fuel from the tank if needed, and then relieve the fuel pressure. Disconnect the battery's negative terminal and raise the rear of the vehicle on jackstands. Disconnect the fuel lines and the fuel pump/fuel level sender electrical connector. For forward-mounted fuel pumps, use a brass punch to turn the locking ring counterclockwise and carefully remove the fuel pump/sending unit assembly from the tank. Replace the old lock ring gasket and, if reusing the original pump, clean and reinstall the strainer. To separate the fuel pump from the assembly, remove the clamp and disconnect the electrical connector. Clean the mounting surfaces and seal ring groove before installing the new pump. For rear-mounted fuel pumps, unbolt the fuel tank straps and lower the tank partially. Disconnect the fuel lines and electrical connector from the fuel pump assembly, and remove the assembly from the tank by tapping the locking ring counterclockwise. Replace the old lock ring gasket and clean or install the new strainer if necessary. Separate the fuel pump from the assembly by removing the clamp and disconnecting the electrical connector. Clean the mounting surfaces and seal ring groove before installing the new pump. For chassis-mounted fuel pumps, relieve the fuel system pressure, disconnect the battery cable, and raise the vehicle on jackstands. Disconnect the fuel pump harness electrical connector and fuel lines. Slide the fuel pump out of the retaining ring by bending down the retaining tab. If necessary, transfer the wiring harness and fittings to the new pump with new gaskets. Wrap the sound isolator around the fuel pump and slide it into the retaining ring, making sure the bracket tabs do not contact the fuel pump body. Bend the retaining ring tab up to secure it. Reconnect the fuel lines and harness electrical connector to the pump. Finally, start the engine and check for fuel leaks.