The upper wing skin is not drilled or dimpled behind the rear spar in the region of the aileron, where the pocket ribs reside. I trimmed the pocket ribs to match the wing skins, after I trimmed the upper wing skins to line up appropriately. Obviously, the trailing edge will need to be riveted, but apparently Mr. Barrows has authorized no rivets between the trailing edge and the rear spar. Nevertheless, I thought it appropriate to put two rivets between. Two dimple the pocket ribs betwen the rear spar and the trailing edge, I used a pop-rivet dimple tool. The trailing edge was dimpled using a pneumatic squeezer. It was necessary to disconnect aux tank fuel line vent line in order to have sufficient room to dimple the pocket ribs.