The under surface of the FAB needs to have a bypass air inlet in the event the cowl inlet becomes plugged. Unlikely with ice in a fuel injected engine but a bird could plug the hole. If I were to do this again, I would move the bypass slightly more fwd. This would allow an easier access point for the Adele clamp that holds the cable to open the bypass. Pay close attention to how the cover plate is oriented. I had mine backwards and needed to fabricate another cover plate.
