That access panel is NOT for a spare tire. I believe it is to access the fresh water tank, if you have to service it. Also, Tiffin did not sell such a part, but if you look at the whole system you have, odds are if you attempted to mount a spare tire to that bracket, you would probably crack/break that rear fiberglass cap and that access panel. Also, unless your photo does not show it, WHERE is the License Plate holder? To the left of the Fuel fill cap? Have you ever changed a Motorhome spare tire by yourself? It is almost impossible to do with hand tools. Breaking the lug nuts is hard even with air tools. But, most people just buy the rubber tire for a spare and that is easier to store inside the storage. That way if you do have a flat and the rubber is ruined, you have a tire for the road service to mount. Doug