This thread has been driving me crazy :crazy because I have done this job before several times (on LT1 engines, just not in vettes), and don't remember EVER having any difficulty with the balancer.
I am currently looking at the STreet & Performance sales/parts catalog. They sell new Corvette balancers, hubs, and spacers to adapt the Impala or F-body LT-1 to the Corvette style accesories.
The center hub is machined to fit tight on the snout of the crank, has a bolt hole in the center for the main crank bolt, and three threaded holes for bolts on the outside part. The balancer hub is round, has a hole in the center for the crank bolt, and three holes for the balancer to hub mount.
There is a pointer/marker on the hub that must be lined up with the balancer ring as the outer hub can be bolted back in any direction on the three bolts. You must pay attention to the parts when they come apart.
Please note that the outer ring should simply pop off the center hub when the three bolts are removed, and maybe the center crank bolt if it has a large washer that overlaps the outer ring.
You should not need any special tools for this. I don't remember ever using a puller when simply changing the outer ring. On the Lt1 conversions I have done, I started with F-body engines, and had to change the balancer to the Corvette for the accesories.
If you put the puller on this, you will in effect pull the entire assembly off including the center hub, then without the correct reinstall tool, you will resort to banging it with a hammer to get it back on. Not good for the crank.
Go back, take a fresh look at this project and see if it aint so.
Good luck,