Are you using vCAC 6.0, or 6.1? In 6.1 we have a script called preparevCACTemplate.sh that automates agent setup on linux.
If you're still on 6.0, you can first check for any installed RPM's, remove them, and then install the new version.
"rpm -e gugent-6.0.1-71.x86_64" should remove the old gugent first, allowing you to install the new gugent.