I can't find the video now, but this couple had mounted their spare under the tongue with a u-bolt that fit perfectly over the middle cross bar. Would go under where your propane tank is. This might be easier to get to if you had a flat as you could put your tongue jack down - jack it up, get the spare off. Your tire may be too big, though.
To mount on the back door - you would have to put in extra bracing etc, right?
To mount on the back door - you would have to put in extra bracing etc, right?