Keith, first off, quit that notion of putting an LT1 t56 in..... its not really an option, and if it was, it would be uber expensive.
The slave cylinder / TOB is the same across the board. I ordered one from GM, one from Tick Performance, and one from napa. The napa and GM ones had the identical part numbers.......... , and the one from tick was a carbon copy. There are literally THOUSANDS of these on the road, with no issues. I would replace the one you have (i know the napa one carries a year warranty - I should "break" mine once a year lol)
You need to start talking with people that actually race t56 cars. Start with Tick Performance - best customer service and knowledge of t56s that I've ever talked to. Go to LS1tech, and look in / post in the manual trans section. Some of the worlds fastest t56 cars live there, and the people that build them.