/mnt /sda1/tce/ is a common and correct location.
Simply use Apps to remove programs
Open Apps, select Apps button > Maintenance > Dependencies and Deletions, wait for the list of installed extensions to be built, then,
Select the Extension you wish to remove, while highlighted go up to the Dependencies button and choose "Mark for deletion" the extension will be listed in the right window along with any errors messages regarding dependencies..
Next select the Dependencies button > Exit Dependency check> close Apps, Apps button > Quit, then reboot
Sounds a little complex when is written but is actually quite easy when you get the routine down.
Hope that helps