Back-riveted stiffeners to skins, along with top and bottom ribs. Riveted shear webs to right side stiffeners. Cleaned the skins and scuffed the trailing edge of skins and trailing edge piece and cleaned again with mineral spirits. Mixed 11 oz. tank sealant and spread approximately half on trailing edge piece and clecoed it to the right skin. Clecoed left skin to bottom rib and began working my way up the rudder assembling the stiffener halves and shear webs, riveting as I went. Finished riveting the bottom rib, including the pop rivet at the aft end, then put clecoes in every hole in the trailing edge. Supported the trailing edge on a straight 4x4 and put another board on top to keep the edge straight while the tank sealant cures.