How to uninstall Unity from Ubuntu?

Hi everyone, I have the latest build installed on my Ubuntu 15.10. In another thread I read that an older version (I think 5.2) is a bit more stable than the current build. I tried to just install the *.deb for 5.2 but the I got an error message telling me that a more current version is already installed. Apart from this I generally like to know how to remove things from my system to save up resources in case I am not using them any longer.

So my question is: How do I uninstall a version of Unity from my Ubuntu 15.10 system so that I can install an older version?

I tried to locate it with the Ubuntu Software Center and also with dpkg but it does not seem to be listet there.

 

Open the .deb installer of the version you want to uninstall with GDebi or similar Package Installer tool, then select Remove Package.

 

Thanks sumauma, I tried with gdebi but wasn't able to figure out how to use it to uninstall a package. But I found the following to be a solution:

sudo dpkg --purge unity-editor