Keep looking, you might find a better fitting clutch disc, but it should work if the hub doesn't interfere. By the way, it's from a 4spd S10, not a 5spd.
Just for clarification,
From your last post, it sounds like you haven't tried to setup anything in the chassis yet??? It's my understanding from other postings on this site, that the 49-54 cars require chassis/floorpan modifications to make the newer trannies fit. If it isn't too late, I would try to mock-up the engine/bellhousing/tranny to make sure its all going to work before I paint anything. I don't mean to scare you by this, as I don't have any direct experience with this chassis, only hearsay. Hopefully someone with direct experience will see this and post a reply to verify this. My first rule of building a modified vehicle (from scratch) is to do all modifications, and make sure they work, first, then do the pretty stuff later. Cutting, grinding and welding are not usually compatable with a fresh paint job.
Good luck with it, I would love to see some pictures when you're done.