This time I worked mostly on prepping the left aileron skins by dimpling them, scuffing the inside, and then painting primer just on the areas where they would be contacting other ribs/stiffeners. This also meant identifying and labelling which side would be the inside, and also taping off the trailing edge to prevent primer going where the adhesive would later need to go. I also spent a little time painting primer on the stiffeners and then dimpling them once the primer was dry. I suppose I could have dimpled them before priming them, but it didn't seem to make much of a difference. Then I started looking at the skins for the right aileron so I could at least label the correct sides there. That also required temporarily setting up the right aileron hinge bracket ribs in their correct position to align the skin with them. Unfortunately this revealed that I had apparently made mistake while assembling those two hinge brackets incorrectly and counter-sunk the wrong sides of them. Basically I had created matched sets of just left-aileron brackets, instead of sets for left and right. Since these are kind of structurally important, simply counter-sinking the other side of them would probably not leave enough strength in the remaining material, so I'll need to replace them. What's next? I'll need to verify this a little more closely, but I think I'll just need to order a new A-1006-1 and A-1007-1, which are about $5 each. Then either finish prepping the right aileron skin, and doing some back riveting of the stiffeners.