Clecoed the bottom and side skins on to get everything squared up.
Match drilled the idler bracket holes through the bottom skin. Updrilled all the rivet holes on the bottom skin, except the front ones. Match drilled the aft bracket holes through the skin and updrilled for the AN525-10R12's at the aft bracket.
To finish the updrilling of the aft bottom skin, I needed to fit the forward bottom skin. I clecoed the right forward skin assembly and clecoed it to the aft fuselage section. Aligned and clecoed the forward bottom skin to the aft bottom skin and updrilled the two skins.
While clecoing the right forward side assembly, I found the bottom half of the holes on F12-05R were nowhere near where they should be. I'll email Sonex to see if I can get another part. The opposite side, F12-05L, have correct holes.