no no...you mis understand...recreate the cover for the rear door, in wood or metal (so you can mount whatever you want 'inside' of the wood/metal cage..
then mount the full size spare on the outside of the box/cage built....basically taking up the cargo space we do have...
say, you had your back seat in, and stood your full size spare up inside your VX behind the back seat...mount it in that area, but attached to the rear door...
you could even use the factory mounting system for the factory spare...that way you always can get the spare unmounted (with the factory lug wrench)
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