The end result...

Wings folded. The trailing edge flaps were also kept movable. The folding braces (parts #E1, E4) were cut in length at their ends and kept "loose" and were not glued on the fold ribs. They can be removed when the model is to be shown with wings in flight position. 

  the open rear door/hatch
The main landing gear, note the tubing lines; also visible is the wing folding "rod" and wire antenna on the bay door.

Some views on the tail hook area

Note the small round fairing below the window

Wing folded... and below in flight position..

Note how the wire antennas run also to the left side next to the observer window.

 Rear view, note the opened rear door

(Note: the wings are movable, this picture did not have the wings "fixed" so you see an edge on the upper wing halve).

A very nice Avenger TBM-3S2 of the MLD is now in the model collection. The conversion can be done without too much trouble provided you are able to make the clear observer window.