Google Analytics Reinstall failure

Hi, I had google analyticator working ok for several weeks. I changed my domain name so I went to google analytics to make a new profile which I did. I have a new google analytics code.

I did not uninstall the analyticator in WP first, but erased a bunch of HTML code (probably an error), which I thought I was suppposed to do then put in new coding.

The google analyticator does not show up now on my pluggin list, however when I go to reinstall analyticator pluggin the system says installation failed because the file already exists.

Goal: I want to reinstall G analyticator and put in my new code. How do I erase traces of the pluggin so I can get a clean install?

Thanks,
Ed