No you will not be able to use that "crescent shaped thing" (Steering arm) Chevy steering box being on the outside of the frame is able to utilize that by running a drag link straight back to that, but FSJ's with the steering box inside the frame can't. Best think you can do is remove the steering arm. Then have the pass knuckle machined for 1 steering arm and then have a drag link made to run from your pitman arm to the new steering arm, Leave the Chevy center link in the original steering arm position, this would be called Cross Over Steering. When you feel you want to go to full high steer you just buy another steering arm and it will bolt up to the already studded drivers side knuckle, then all you would need is a custom center link and have your drag link shortened.
Daily Driver 2008 Wrangler Sahara
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