Anything that the manufacturer and/or government regulations designate as the main body. Data plate above the door 1 Left, VIN plate under the front windscreen, engine room firewall, metal plate embedded around the magazine well left side, framed certificate hanging on the wall, a consecrated amulet placed somewhere in the lower deck, doesn't matter. Everything else are parts, which can be separately defined and controlled as dangerous items if need be. Generally that works.