Withe the top skin installed it is time to rivet the top skin and leading edge skin to the aileron spar. Before starting, you are to attach something to the top skin to keep it straight.  I have an eight foot length of 1.5 inch aluminum angle that I got from Home Depot that I use for this kind of thing.

Holding the bucking bar in one hand and the rivet gun in the other, I can do the riveting by myself. The last picture shows some of the misc. rivets that attach ribs to the spar.