[Scott]

I've got mine put in the spare tire location. It's not a 12", but it fits nicely. Only problem is figuring out what to do with the spare, as it's not a great idea to travel far without one.

The other option is in the trunk. There is the recessed area where the scissor jack and tools go. You can pull that out and make a nice enclosure that fits perfectly flush in there. Every once in awhile, pre-made boxes in that style pop up on ebay.