Dan, the door in the pics is two pieces also. Note how the rear (trailing edge) hatch cover is hinged to the main cover, upright in the pic. It's folded back, displaying the upper (outer) surface. When the covers are closed, the smaller (trailing edge part) is hinged back up, and drops into the top of the rear part of the open bay.
The space between the bay and the open ammo access hatch, is also three separate hatch covers, running span-wise, each covering an ammo belt track. These would be removed, independantly if required, as separate, loose pieces.
Try to get some pics of the kit top wing in the hatch area, the parts for the hatch covers, and the parts for the bays, along with the drawing on the instruction sheet (or e-mail them to me) and I'll do a sketch of how the bay, fittings and feeds are constructed, so that you can compare with Paul's and Corey's pics. I can also do suggestion sketches of how to construct door and bay detail etc.
I'll also be able to see if the 'Flexi-Feed' chutes I have will be usable when modified. From what I've seen so far, they will be.