I only needed a little bit of tweaking/sanding maybe 1/16 on one side of the galley flat. This was mainly due to some extra thickness caused by my taped seam. What I learned is #1 DON’T force it or you risk the veneer on the bottom of the galley flat blowing out. #2 make sure you take out any copper stitches that my be in the way…I took a few extras out of the side so the shell could flex a little more. #3 lift the lower side of the galley flat about 1in from where it is in your picture. Have it sit at the apex of the glass joint (the widest spot of the shell), then slip the higher side down.