if one wanted to do this install/upgrade purely via SSH at a remote station, what would the commands be to download the package and uninstall the current install?
To download files, use wget:
wget http://www2.ati.com/drivers/linux/ati-driver-installer-11-6-x86.x86_64.run
To remove packages, use apt-get:
sudo apt-get purge fglrx fglrx-amdcccle fglrx-dev