DJ Jazzy, This is why I had to mount my spare under the trunk floor:
I saw your spare tire mod before I did mine. Thought about mounting the tire under there, but didn't want to cut into the air diffuser, and get nearly under the car to lower the hinged panel and tire when needed. For me, the false cargo floor was the easiest to build, and if ever the spare tire is needed, it's a quick and painless way to get to the spare tire. Just lift out the false cargo floor, and the tire is right there. But your mount is a great idea, especially since no trunk space is lost. Seldom do I have a lot of cargo where I'd need that lost trunk space. I'm easily able to lower the seats, and get my bike in the Leaf without issues, in fact it's now easier to get my bike in the car, since the cargo area is raised up about 6 inches. Now I never have to leave home without a spare.