I had originally made the two-piece bottom cowl with cutouts for the carb/air box and carb air inlet in order to maintain maximum structural integrity. Unfortunately, that would necessitate removing the air box and carb heat ducting and linkage in order to remove either side. That being the case, I decided to enlarge the cutout so removing the airbox and ducting would no longer be necessary to remove either side. That required a flange, which ties into the aft cowl flap bulkhead, and also connects together at the front. I also added a flush oil drain door using a Camloc single button latch.