VFP9: Install SP2 Final over its Beta

You CAN'T!

Neither SP2 CTP nor SP2 BETA have uninstallers. So, have in mind that you'll need to reinstall VFP9 when you want to update or go back to SP1 for any reason.
Source: http://weblogs.foxite.com/vfpimaging/archive/2007/08/11/4520.aspx