I bought a 1999 camplite U10 pop up by Damon, the entry door is two pieces with the bottom half fixed and the top part swings up and mounts to the ceiling for lowering the top. My issue is the top half of the door has a u- shaped channel on the bottom that slides over the bottom half of the door when you are setting up the camper. the bottom half has a weather seal across the top of the door. When I Lower the top to let the top half channel slide over the bottom half to lock the doors together the side frames on the top half are bottoming out on the side rail. I can stick my little finger through the corners because top half isn’t coming down enough to close the gap and the door frame want let you lower the top anymore. This is making my canvas on the right side of the door to short to slip in the rails, also you have to crank the top up so high to get the channel above the lower half of the door before lowering it in place it pulls the canvas out of the groove.so my question is do I cut off about 1/2” on sides of the upper door so you can lower the top and it will let the top come on down and sit on the weather strip of the bottom door which will give me slack in the canvas to get it in the grooves, plus I want have to crank it up so high to get the top door in position to lower over the bottom half and it want pull the canvas out of the track. The top half of the door is mounted with a hinge at the top and there is not enough to lower the door any it has to stay mounted where it is. The only choice I see is cutting the sides to let the top come down 1/2” inch. I’m pretty sure it’s the original door because it has a sticker with the year model on it. Should I trim the bottom of the upper door frame.