F450 or F550 spare tire placement

We are in the process of trying to figure out where to place a spare tire on either a F450 or F550 pickup that will be carrying a truck camper. The spare tire needs to be located under the body of the truck due to the placement of the gas tank we are stumped. Does anybody have any suggestions/ideas?

Thanks for your help!
F450 or F550 spare tire placement

Have you considered a front mount? I had one on my '87 Chevy for 13 years and never overheated in 179,000+ miles.
F450 or F550 spare tire placement

The front mount is starting to look appealing. As you mentioned, our first thought was that it may hinder airflow through the cooling units.

Roughly how much distance is between the spare and the grill on your '87? Did you add an electic fan or has the factory set up kept her cool?
F450 or F550 spare tire placement

I found a site for the Centurion conversion company where they move the rear mount F450 fuel tank to the mid-ship F350 position and put the spare under the tail like the F350.

Anybody seen one?