Tamiya Tank Interiors?

The 1/25 scale Tiger I has a complete, but rudimentary interior.

The 1/25th scale Tiger I includes an interior. Simplified, but it attempts to represent the full interior. Not much in the smaller scales. The 1/35th scale Sturmtiger has a reasonably complete fighting compartment interior. The engine is sold separately, but there is no radiator detail. The 1/35th scale open-topped US and German halftrack kits include interiors of the troop compartments but not the engines. The 1/35th scale King Tiger with production type (Henschel) turret includes some interior detail, including the ammunition racks in the turret bustle and the gun breech, but nothing below the turret ring. The early (Porsche) turret has the gun but not the racks. Recent Dragon German tank kits have generally included turret interiors and sometimes the hull machine gun mount is included. The Tiger I kits have the engine compartment detail visible through the deck grills, but not the engine itself. Same with the new Smart Kit Panther G and the Premium Edition Panther D. Academy has been offering interior detail in many of their kits, including some versions of their Tiger I kits (marked "Interior Model" on the box), though it suffers overall because the turret shape is incorrect. They offer fighting compartment interiors in the M3 and M3A1 Stuart kits, as well as their M18 Hellcat and the new M3 Lee. Gerald Owens