Lower Turret, Bull Session. Cleaning, Cataloging, and restoring.
Debris brought from the field site, stays in storage until ready for processing. Each and every item will be cleaned and examined for numbers and then identified. All data obtained from the item or identified by comparison is then added to the cataloging system. Once everything is photographed, cataloged, and tagged the work begins to assemble the pieces.
Here, the pieces are clustered into like items, or associated parts groups. In the photo, the groups are Shell sections (Door, Center, Top, Trunion support, and side trimming).
There are also internal pieces present that will be separated for positive identification.
These processes can take several months as this puzzle does not come with a box, but thanks to a huge number of people out there uploading really great detailed photographs of the ball turret in and out of the aircraft, as well as completely disassembled or in restoration, this helps immensely. Pouring over the parts catalogs and maintenance T.O.s is key to verifying the numbers and explaining the function(s) of the parts or sections.
Some fragments of the frame and shell are also found in the plowed field that eventually mates up with the larger pieces taken from the dig. The concentration of parts on the surface also aids in pointing out where the lower turret most likely hit the ground or was lying at in the field, it can also reveal a pattern of debris field. This will be helpful in determining the direction in which the craft came from.