Honestly, I really thinks it depends on the driver. Last time I was up there, I was told by somebody coming back down that I wouldn't be able to make it in my lifted JKU Rubicon. Given that the guy was driving a Toyota I took it with a grain of salt and made it over the top with no problem. It certainly wasn't one of the tougher trails I've been on.
However, I have zero experience with ZJ's, stock or otherwise. You need 4wd, low gears are useful but not necessary (or rather, weren't necessary for me) and you'll need good route picking skills and some clearance. It's not a trail you can just drive straight up. I had to pick my way around and over some obstacles, and you'll need to do more of that with your ZJ.