You dont need 11c48 - the package will install the kexts from that build anyway. The only requirement really is that you are running lion.
The native package should work regardless of your chameleon build being 6900 series friendly or not (not many builds are that I know of other than ones that I have built myself or shared on here) so you have at least picked the right package.
Alright, well I will give it a try tonight. Would it make a difference if Windows is installed on a different HDD? Or that I have a couple of bootable backups of Snow Leo and Lion? I just always assumed no, but I figured I'd ask since I have your attention.