Just changed mine today because of wobble (174,000 miles). To remove the original bolt, I heated it with a propane torch for a few minutes, then my stubby impact wrench zipped it right off. Used the tool mentioned above from Autozone, to remove the damper, it worked great. Replaced the front main seal also.
Getting the new balancer on is a pain in the ass. You've got to "persuade" it onto the crank far enough for the bolt to be able to engage the threads in the crank, then you've got to come up with some way to prevent the crank from rotating - there's nothing on the front of the engine to wedge a screwdriver or extension or bar or whatever, but since my car was up on a lift I was able to remove the small round metal inspection cover at the bottom of the transmission bellhousing and blocked the converter from rotating with an old screwdriver against the side of the hole.
I tried using a "balancer installation tool", but the center jackscrew was too large in diameter to fit into the crank snout, and not long enough to engage the crank threads, so once I had managed to get the balancer far enough on the crank with a few love taps from a deadblow hammer, I used the old bolt to pull the new balancer into place, and cranked down on it to about 240 ft-lbs to fully seat the balancer. Then I removed the old bolt (again), put some red Loctite on the new bolt, and fastened it to 37 ft/lbs. That was easy enough, but the next part wasn't - tightening the bolt an additional 140 degrees of rotation. Doesn't sound like much, but it took my big breaker bar, a length of cheater pipe, and just about all I had to get the bolt rotated that much.
I freaking DESPISE TTY hardware, the bull**** procedures you have to follow, and the waste and expense of throwing away hardware after only one use - all because GM thought they could save a few pennies per vehicle by not putting a keyway on the crank snout. Yes, I know I could upgrade to an ARP bolt and just torque it and be able to reuse it, or pin the balancer to the crank to keep it from spinning (I've done both on other LS engines), but the point is, we shouldn't HAVE to do all this crap just to keep the crank pulley from flying off. GM *****ed this **** up, and that's the truth.