two versions of FS on separate Hard Drives?

I have installed two versions of FS on my PC and they do work independently, one on my C: drive (which was the original weighing in at around 25gb), which has the 733NG and 744 installedTo enable me to install another copy of FS I did the following:-I renamed the .cfg and .exe files to FSold.cfg and FSold.exe this then enabled me to install a second parallel version of FS on my new F: drive. I have now discovered that the new version does install a new .cfg in the C: drive (which is not a problem) so they are all working ok? The only trouble is that add-ons like the PMDG 737 series and 'the Queen 744' can only be installed on one version; when I try to install another copy, I receive a warning message saying that this product is already installed? - is there a way round this, so I can have both a/c on the two separate drives (C: and F ? The same goes for Active Sky is this possible to have two independant versions?Could I create a new profile and install these add-ons again to my F: drive? would I then be able to logon as my normal profile and still fly these a/c from the installation on the F: drive?Kind RegardsPHIL