If forgot to take pictures of how the trailing edge is built, but the plans have all of the information you need. I also finished sheeting the bottom of the wing. The bottom sheeting comes flush to the trailing edge, but the top is a little tricky. I haven't begun to built the flap pockets yet. To prep the wing surface for sanding, first I ran a damp sponge across the wing to help lift some of the small dents up. When it was dry, I started sanding to make everything even and smooth. Then I used a old credit card to put on a thin layer of DAP light weight spackle to fill the pin holes (there's hundreds of 'em) Now its ready for final sanding. Most of the spackle you see there will be sanded off leaving a smooth wing surface thats ready for fiberglass.