In order to get more space inside the turret, I needed to cut some parts out.
The turret is composed of 3 main parts, the top part which is te main turret which holds the gun and the crew doors.
The second middle part is like a spacer that locks the gun in place and serves as second deck. Unfortunately I have started cutting out the half deck before I took a picture, so this item had already been cut of the deck I am mentioning. I will try and locate another photo online.
Lastly the third bottom piece is the one that rotates on the upper hull, it holds the floor for the figures, with out this the main turret will not lock in place on the upper hull, here it is.