bridging wpmu and wp

Okay, so I just moved my biggest blog and info, but I forgot that I wanted to install on my wpmu compatible server (media temple). So I was going to install wpmu into like: blogs.defaultprime.com, then have the blog url’s be like: blogs.defaultprime.com/user1. But, I don’t want to leave out the 350+ registered users on my blog, so I was wondering if there was some way to hack wpmu so that it would draw information from my _users table for my regular WordPress installation. I’m pretty sure I can do it, but I just want to make sure because I don’t want to f*** up my server and installation again (blog’s about 4gb’s big).

Thanks for any help,
SuperMario290 (keenan payne)