The M113. Old School Tamiya kit came with a complete, and fairly accurate interior for a Nam era Papa Chuck. While it needs some detailing to bring it up to modern standards, the old kit included the engine, transmission, interior and a removable roof to allow full view. I remember it not having a radio or radio rack, that's about it.
Academy issued a more accurate, but closely copied version of it later. I do not recall if the Academy's version had the removable roof or not.
When completed, it's almost like looking into a little shoe box with the lid off to see everything inside.