You need to lightly lubricate the new
Fuel Injector O-ring seals with mineral oil GM P/N 9981704, and install the new fuel injector O-ring seals onto the fuel injector. Then you need to install a new retainer clip to the fuel injector and push the fuel injector into the rail socket with the electrical connector end facing outward. After that, you need to connect the fuel injector harness electrical connector to the fuel injector. Finally, you need to install the fuel rail assembly.