Dimpled center section bottom skin then deburred the edges, cleaned and primed. Worked on skeleton by repriming some of the scatches and then trimming the seatbelt brackets that interfear with the ribs. Rebolted the brackets in place. Then I deburred,cleaned and primed the crotch belt brackets. Clecoed the bottom skin in place and started riveting. Only about 30% done tonight. Probably a couple of hours left to rivet.