Clecoed main ribs to forward spar and prepped the assembly for riveting. Plan to have Steve come over this weekend to buck rivets! After doing some research, I've decided to reverse the order called out in the plans and rivet the ribs to the forward spar first -- this will allow me to gently flex the ribs out of the way to avoid damaging them with the rivet gun. The pictures show the tape I've placed on the spar to protect it from the bucking bar, and I've done the same thing on the ribs.