I made the decision to leave off the bottom wing skins till the last, after building the ailerons and flaps and sorting out the aileron drive. I started the left aileron by pulling out all of the aileron parts and removing the blue plastic "skin" from each part. Then, I cut out the 36 aileron skin stiffeners and trimmed, sanded and polished three of them. I'll do the rest later.
Left aileron parts laid out
First three aileron stiffeners set in place on the aileron skin