Part of that longer wheel base is that they move the rear seat back a little bit (1"), but it helps. Then there is the "cavernous" (when humorously compared to a TJ) space behind the rear seat. My LJ's butt drags on rocks all the time on harder trails, but it can definitely wheel with the TJ's just fine. The difference is, after driving home, my kidney's haven't been pulverized to jelly, unlike the TJ guys. The ride really is that much better!
There is a LOT of room in the LJ when you pull out the rear seat!
And enough room even with the seat in to actually store stuff:
(note, the gas can was just a trial fit, I keep it on the tire rack in back: