virtualbox.org

Maybe I've got a mental & search block, but I can't see how to uninstall Guest Additions in Linux (Ubuntu 12.04) Guest OS.
I can't find anything in End User or Technical Docs here.
I can't find anything in Community - Forums - Linux Guests.
Dash Home shows nothing for 'virtual', 'guest' or 'addition'
I can't see them in Synaptic Package Manager nor Ubuntu Software Service.
Something shows under System Settings - Hardware - Additional Drivers ("x86 virtualisation solution - guest addition module source for dkms") but they're not activated.
Loading the Guest Additions ISO allows me to install - ironically uninstalling first but then immediately installing without the choice of stopping in between!

Any advice or pointers would be appreciated

Aha! After looking deeper than the initial search results, I have indeed found the answer in the forums.

sudo apt-get purge VirtualBox*
sudo apt-get purge virtualbox*

I suggest adding the uninstall steps to the FAQ and/or Docs