Several years ago, ( probably about 50) after we ripped the side mount spare off on a tree, the fellow who helped my dad with equipment maintenance on the ranch came up with a similar solution for the spare. I have since replaced the side mount, but left this on "just in case"

The other section has the center part of the hinge along with the wheel mount bracket and the upper part was bolted through the tailgate. You could swing it down if you wanted to open the tailgate.