That's crazy and bad ass. (excuse may language)
It has a bicycle chain drive with gears (see derailleur). Full size spare on the back.
And the best of all, the JEEP logo.
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I was still searching around the internets and ran across this TeraFlex 3rd row seat bracket for putting a 2 door rear seat in the back of a 4 door.
It's a little pricey $$$.
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I understand what your getting at.
The problem with the 2 door rear seat is it uses 6 heavy steel bars/brackets recessed into the floor to mount on (see pic).
You would have to make those or find some other way to mount the 2 dr rear seat in the flat storage area in the back of you 4 door.
a...