Delivery times with Glenn used to be a problem, not sure if they still are. He's busier than a one-legged hooker in a $1 all you can get brothel.
I used to run the Trail Tough SJ413 rear springs up front, CJ fronts in the rear on my Sami. Was the best suspension combo at the time and it was my 6th variant of the suspension, was also the last because with the right shocks and mounts I could acheive 45" of articulation and it rode like a caddy.
Steering: GO knuckle over! Don't bother with anything else. In fact do that with any SPOA conversion.
Panhard rod: I feel would be neccesary because of the length of the springs to keep on-road steering feel normal and keep off-road steering controlled. I ran one on mine and it didn't do much on-road but off-road steering response was MUCH improved, turned on a pin head!
I've only seen the YJ leaf conversions in person, never rode in them but they seem to flex better than my old setup. Couldn't comment on ride.
Your driveshafts will most likely need to be lenghtened because it pushes the axles out quite a bit. For the rear get a high angle HD CV system and the front might be passable with 2 spacers.
The review I did of TT missing link system is still up on off-road.com. I later removed the missing links and installed 3" long shackles, off-road the chattering was bugging the crap outa me. Flex didn't degrade either.