Removed protective vinyl from and deburred aft bulkhead. Clamped center section aft bulkhead to centersection assembly as directed. Removed protective vinyl from and deburred bottom skin. Clecloed bottom flanges of bulkheads to bottom skin. Temporaril loosened the clamps holding the center section aft bulkhead to the center secyion assembly to allow the parts to re-align according to their being clecoed to the bottom skin. Re-tightened the clamps.
