Some M3 types , mortar carriers and SPGs , did have stowage boxes of various sizes or racks either side of the rear door, so those parts are great for us kit bashers . I'm thinking the second type of 50 cal ring was an IDF modification post WW 2 , I don't see any of that type on the WW 2 half track pictures in my books . Aside from that , the kit parts look great .