Downgarding from Norton 360 to NIS 2012

My subscription to Norton 360 will soon expire. I only want to get NIS 2012. Is it best to do this as a download, or via CDs, or ...

 

Should I uninstall Norton 360 just before installing NIS 2012?

 

(Of course, Norton only provides information about buying a more expensive product, not downgrading.)

 

Thanks ...