The windshield bars and seat belt mounts will need to be addressed since the CJ bar doesn't go to the floor. The side of the body also mounts to the roll cage near the striker plate. The TJ inner fender is too roundy for the CJ roll bar platform. You would be modifying a safety item so this might not be a good idea but... I would cut off the rear loops and weld in diagonal (CJ- like, early wrangler-like) bars using the same mounting flange. This way you would have the factory seat belt mounts and windshield bars. Someday I might do the same thing
Best of luck - John