I believe Sharon has a center rising roof that might give some interesting ideas! I think it is cool taking a classic icon and making it into something usable! Just like the Road Rocket, Roswell, Gypsy Wagon, Etc.
So why would it need to fit in the garage? Any flexibility in that area maybe? When I first was reading it I thought you might have meant literally like Spinnernut's trailer he pulls behind the teardrop (A literal caboose so to speak)... So going along those lines..... Maybe... this could be something that could be a REAL caboose that looks like a caboose!! Your mockup of course in Red and White made me think of it.. and in miniature form, you could use it for alot of things... A smoker with the roof being the lid, or a way to transport some little cycles or who knows what??? Just thinkin out loud...
