A slight update to the engine/radiator mounting frame, I have added the two U-channels that reinforce both ends of the structure and added the side bracing flanges.
Here you can see better the bracing and attachments to the hull side walls. I have loosely place a piece of tread plate to show how I think it looks, I think the tread plate should extend right up to the gearbox to allow easy egress of the vehicle through the rear escape hatch.
There are ammo stowage racks found under the tread plate.
An above view.