Win7/64; 9000 running 4.6.304; DM 6.0.1.18.

I want to upgrade to 5 (1049). I was running 822 and bailed on that when the ring tones stopped working. In the process of downgrading to 4.6, "Blackberry Device Software" disappeared from my "Programs and Features." (Add/Remove). All the files, however, are still in Common Files.

1. When I upgrade now, I assume the new OS will overwrite the 4.6 files in Common files, correct? Or do I have to delete them before installing 5?

2. Will the 5 upgrade also repopulate the uninstall list in Add/Remove? If it doesn't, and I want to return to 4.6, I can't go back without uninstalling 5.

Thoughts? Thanks.