Next, install the new shooter(s). Ensure the throttle plates are closed. Before you drop them into place, be sure that the needle check-valve is in the shooter discharge passage. The check valve installs pointy-side down. The shooter can now be installed; be sure to install the hardware in order. From left to right: shooter screw, check valve, shooter screw gasket, shooter (or discharge nozzle), discharge nozzle gasket.