Lost cause, yeah. Plenty of modern diy sub options more worthy of your time. Rehabbing that old rat shack sub would require a pretty deep dive into speaker engineering. I support you in doing that, it's a great enhancer of our hobby to understand how it all works and build stuff you'll enjoy the heck out of. But that driver is probably the last thing you would want to use. Even if you know the t/s parameters, design the appropriate enclosure, and actually build it, the results will only be as good as that cheap 30 year old driver can deliver. If you're going to go to the trouble, make it worthwhile.