Is there a source for part #23881 in the L4 greenhouse, or will I have to make my own. Can someone give me the correct dimensions for that part? Question #2. Is everybody actually putting a 3/16ths inch gap between the front of the top door, and the front channel on the birdcage, (sorry I don't have the part # in front of me). This is what I read on the blueprint, but seems excessive. You can throw a cat through that gap! Building my own fuselage, but want to keep it close to the original. This site has been a great source for information. The people that have published their build progress have been an inspiration and a constant source of information and talent. Any help is appreciated. Jon