Uninstalling PGI Workstation on a Mac

Hi-

I am in the process of installing PGI Workstation complete on Mac OSX 10.5, but I have an old Trial install of PGI Workstation 8 on the system that I had forgotten about

How do I remove the old installation? I did not find an uninstaller and I am seeing parts in atleast 2 directories: /opt/pgi and in /Library/Receipts

Thanks for the assistance!