Finished deburring the bottom skin/gussets/stiffeners/longerons. Treated mating surfaces of skin and stiffeners/gussets, but not longerons as they get removed at least once more. Riveted the stiffeners/gussets to the skin. Flipped the skin and positioned the rear side skins and rear HT panel. Drilled #40 holes in the longerons to set final position. On the left side I had just barely enough longeron so when it gets trimmed later it can follow the profile of the rear side skin. Not a lot of wiggle room when it comes to positioning the longerons, but apparently it is best to give more liberal overhang on the rear than the front. Disassembled the rear side and HT panel and set aside the bottom skin assembly.
Starting on the side skins. Unwrapped the side skins and moved the one I marked as starboard to the work surface. Cleco'd the appropriate rear side skin. Removed the starboard longeron from the bottom skin assembly and moved it to the work space. Should be able to fit and drill that tomorrow.