I can't recall how much you would need to remove - obviously the front tiny screws through the flap, not sure how much more to get the ramp able to be lifted enough to work under it. You then fill your balloon with the epoxy (slow dry) and screw the ramp back down exactly as it would be if fully fitted in place. This will squeeze the balloon and create the exact mold to fill the gap under the flap. Next night loosen the screws, trim the excess balloon each side and then screw back down.
