Never personally done exactly what you are attempting, but there shouldn't be any magic to it...........all you are doing is reversing the process of installing one. The sawzall with good sharp blade, maybe an air saw, and various grinding tools to finish off the job should be all that you need.

I would remove as much of the interior as you can to make room and prevent damaging them, then cut it up as close to the floor and into as many smaller pieces as needed to extract it from the door openings. I would think that removing a lot of small pieces would be advantageous so you can nibble it down to the top of the frame. Then you can grind the remaining stubs down flush with the floor.

Depending on how it was all installed in the first place, you may not have much repair work to do to the floor and surrounding areas, but if they cut it up a lot to get it in there you will have more work to do.

Just out of curiousity, how is the rollbar preventing it from being streetable? Access to the interior? Maybe you can just remove some parts, like the door bars so you don't have to climb over them every time you enter and exit.

Don