Unclecod the aileron from the board after a few days of tape curing. Back-riveted the double flush trailing edge. Came out really well. The tape method is a success.
Pulled some of the mounting hardware and temporarily mounted to wing. This is done for now. Will permanently mount after the flap gap fairing is installed.
I did realize that I made a mistake, but I think it is just a cosmetic one. The pull rivets on the end rivets are supposed to be CS4-4s and I used LP4-3s. I was looking for those rivet callouts in the plans and couldn't find them. I should have remembered the 120 degree dimple dies though. I ordered some just for these rivets! Oh well, doesn't look bad. I'll probably do the same on the right aileron to match.
8/28: the more I look at it, the left aileron has a slight bow to it. I put it back on the board and sure enough it sits about 3/32” high in the middle. Worse, there seems to b a slight twist. I drilled out about 2/3 of the trailing edge rivets and tried to fix it. With everything drilled out, it was laying flat again. Then I redid the back rivets hoping it would come out better. Put it back on the board, twist is gone but it still bows 1/16” or so. Better but not perfect. Calling it good.