Office 2007 deployment via GPO

HI,
We have a network of over 60 users in house. Some users are running off2k7 and some of 2k3. We want to deploy 0ff 2k7 through gpo and at the same time automate the unistall of off2K3. I was not able to find any thing stable to implement this.

As always thank you very much for the help

Aamir