About this detail of the Tiger
The "Bergepanzer Tiger" originally had a toolbox on its rear wall, like all other Tigers since 1942. The toolbox was held in a welded metal frame.
When it was converted to a "Bergepanzer", another frame was added to the rear wall, for holding jerrycans. The toolbox could no longer fit in the original frame, so the original frame remained empty.
The best model kits of this vehicle do not accurately reproduce the toolbox frame. As this photo shows, the frames are provided as photo etch parts in both Rye Field and Dragon kits. But in each kit, the bottom of the frame is solid.
As this photo shows, the real frame was open at the bottom.
Rye Field have made another error in their kit. They have connected the jerrycan frame to the toolbox frame.
As this photo shows, the real frames were not connected. The Dragon kit has separate frames.