First of all, to replace the fuel pump, relieve the fuel system pressure, disconnect the battery, remove the intake manifold, undo the electrical connector attached to the high-pressure fuel pump, and remove the wiring harness bracket, and the fuel line. Use a wrench to remove the high-pressure tube, but when you are loosening the bolts, take caution due to the intense pressure. Then, remove the lifter guide, the spacer gasket, and the O-ring. For the installation process, mount an O-ring onto the pump and rotate the crankshaft to the proper position. Then, install the lifter and guide it into the housing, align the key to the groove, install the spacer gasket and lifter guide to the valve cover, and line up the fuel pump bolt holes. Also, before fully tightening the high-pressure fuel pump bolts they should be tightened by hand, and install the high-pressure fuel tube. Finally, you can tighten the high-pressure fuel pump mounting bolts and the fuel tube nuts to the proper torque.