John
I made the location of the upper aileron horn the same as the one on the lower wing. This still gave some differencial 1" lower wing and 1 1/4" top wing up and 7/8" lower wing and 1 1/8" top wing down. I also found that is too much movement for my airplane and will reduce it the next time I fly it. As for the wheel pants I also added another piece of ply but used blind nuts and went to 4-40 bolts with washers and lock washers(note: you have to drill out landing gear holes for the 4-40 bolts). So far that seems to keep them tight. Hope that helps you.
Roger