If I remember right, the last time I did it I removed the 3 bolts holding it on and just tapped it from the back side leaving the hub on. Just take a block of wood and tap it from behind. It came off fairly easily. I was replacing my optispark/water pump. Be sure to reference/mark where the balancer comes off (mark 12 o'clock position) and replace it in the same position. I tried using a 3 jaw puller but I couldn't get it off with it. I bet GM has a correct "tool" but I got that info off of a post from
www.cz28.com in the LT1 tech section. Here is the correct way to pull it:
http://shbox.com/1/pull_pulley.jpg . I installed it by aligning it back up and using a block of wood and a mallet. Not technically correct but I didn't get to crazy with the mallet either. No problems with mine so far.