Are you guys going to push the rear axle back at all? You could use a Long wheel base rear drive shaft.
I was thinking about doing this to my kick. Not that far back, but like 2 inches. I was going to cut the lower bars and sleeve them and then build a new upper "Y" bar. To keep the springs in alignment I was going to do the overrotate and move the spring perches forward like they are on a jeep TJ...
Just some food for thought..