I read (awhile ago) someone recommended not gluing the cardboard tube inside the fuse. This way you can remove the tube and pull the tank out. I just finished building the wing panels myself. Will be starting on the fuse soon. I may look closer at the tube idea myself. A guy could even use elastic bands on the female tube and then just push them out to either side touching inside the fuse sides. Interesting idea, may take more strength away then the hatch though!