Made a little more progress. Riveted the F-826 and F-827 mid-bottom skins to the center section aft flange and the seat rib sub-assembly. Torque'd the two bolts in teh front seat ramp support angles. Didn't get quite as far as doing the double row where the skins overlap with the F-824 aft skin and attach to the F-807 bulkhead. That we'll tackle another night: Jackie and I both have studies and exams so we're pretty busy bunnies right at the moment...