"Already installed" error in Joomla 1 click

I tried to install Joomla and got an error that it was already installed. I discovered that Joomla had previously been installed under the wrong user name. I checked the wiki but did not see a way to uninstall other than to delete all directories etc. I ftp’d and deleted all the Joomla directories, and deleted the sql database used. I created a new sql database and retried the install with the same results.

So, how can I install under the correct user? Is there something else that needs to be deleted or reset? Or is it a case of letting the dust settle from the previous deletions? If so, how long until I can reinstall?

(Never mind - found Manage Installed Applications - sorry!)