Ailerons pretty straight forward on riveting except the upper skin/spar rivet line. It took a couple days to think through this. What I came up with is to gently pry open the skin (need to carefully re-orient the bottom skins and block with a piece to 2 x 4 on each end, then rivet and buck rivets. After finishing all the rivets you have to carefully realign the skin orientation to have the bottom skin resting on the inside surface of the forward skin piece. It can be easily done...just take your time.