Merkava Armor Question

So today I was looking around at some pictures for the Merkava Mk.4s and came across some images that show the cutaway of the turrets composite armor composition.


image
IMG_4467
IMG_4468
My question is where is the backplate shown on these cutaway images in war thunder’s model, and why is there barely any open space in the composition compared to the x-ray for the composite armor in war thunder. The war thunder x-ray shows a good margin of open space as well as no model for the composite back plate as shown in these images.


Could someone tell me where this backplate is and why there is so much open space present in war thunder in between the composite armor and the turret superstructure, I may just be stupid but it seems like something big is missing with the Merkava mk4s turret model.