Alex, nice interior details. Are there no hatches to leave open?
This is what you get when you add the upper hull. This isn't the kit's fault, it's depicting the vehicle.
(A) only lets you see a sliver of the top of the engine. If you wanted to show it off you'd have to remove the cover plate. If they molded the plate separate it would take care of it. That would be removed for maintenance or display.
(B) actually shows alot, but this hatch also serves as the mount for the radiator. You probably wouldn't see that open except during maintenance..or for display
(C) is the rear hatch. It's a small hatch, measuring under a meter squared. The rear compartment is about a meter high. If you open the rear, it's going to be dark, limiting what you see. Myself, I think this would be a neat place to depict the crew using to sleep and stow gear.
(D) this one works well. All you can see is a crude driver's seat. The opening is small enough that a driver figure blocks any view inside.
I applaud Trumpy for including the interior bits. It's a great start if you want to go bonkers on an interior or enough to hint at what lies beneath. For my simple build, it's wasted. This time next year this might be re-purposed to mount a surface-to-air missile launcher.