I did this a couple years ago. Yes, you have to unbolt the motor mounts (easiest at the chassis). You also have to disconnect the throttle shaft on the engine and the tie rod on the OD. I lifted the engine with a floor jack and a 2x4 under the pan, which left a nice impression of the 2x4 on the pan (didn't cause any problems, though).
Your biggest problem will be getting the large nut off the balancer/pulley. You have to 'lock up' the engine and use a) a large breaker bar and socket b) the starter or c) a 3/4" impact wrench which doesn't really fit between the balancer and the front chassis cross-connect. (a) and (b) didn't work for me, but (c) did with some finagling. If your water pump has 50K or more miles on it you should consider replacing it while you're at it, but I dunno a reliable source for a new one (Michael Salter does good rebuilds). Check your timing cover seal--you'll want a new one with a new/rebuilt balancer--and timing chain tensioner while you're at it.
Why are you replacing the balancer? They can be rebuilt.