Roll out Microsoft Office 2010 Via GP

Hi, hopefully someone can advise of the following and save me time and user trouble.

On my network I have around 70 installs of Office 2007/2010, I need to install office 2010 to get everyone onto the same version.  Some of the users are remote and come into the office only once a month at times.

Rather than remove each office 2007 version individually, how can I get a Group Policy to uninstall and then reinstall unattended from a network share.   I have a few more considerations to be taken into account, we are in a secure environment running Symantec PGP and as such I would need to have a cmdline script to also run to get back from any reboot by bypassing a PGP pre-boot login screen.

Also to uninstall the 2007 version I have to stop the Trend AV clients as this prevents part of the uninstall when running.  I will also need to repackage the install MSI to incorporate the license key, I assume this can still be done on 2010 and remember a few years back doing something similar on 2007.

Initially I would want to test with a couple of machine in a OU by themselves, to ensure there are no problems prior to rolling this out.

I am sure there are many other considerations to be taken into place and that’s why I am asking in here.

Thanks in advance for everyone’s assistance