I just did this last week. Its not too bad as long as you don't have a problem getting bolts off. You do need to remove the power steering pump and the pump mount to get to the water pump though. There's no need to disconnect the hoses though, just kinda move everything out of the way. I got it done in a few hours with no major problems. I also replaced that heater hose pipe that 'my litte red YJ' referred to. I'd also recommend flushing out the coolant system before you take anything apart so you don't have to deal with coolant while you're under the hood.
1992 YJ, 2.5L 4-banger, 2" Lift, 31x10.5 BFG Mud Terrain, K&N Filter, Restrictor Removed, Hi-Lift, Custom bumpers, More to come...