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Forum Moderators: travelin cat
If so, you should be able to run the installer again and choose "Uninstall." If that option doesn't exist (been a while since I ran the installer), then check the README for details on what gets installed where, and start deleting stuff.
At least, I think that's the purpose of the  part of this line:
RECEIPT=`ls -1 /Library/Receipts/ ¦ perl -n -e 'chomp; print "/Library/Receipts/$_\n" if -d "/Library/Receipts/$_" and /mysql-(standard-)?
/' ¦ tail -1`
I would ask about the shell script and it's suitability for removing MySQL 5.x in Marc's forum [entropy.ch]. He and others familiar with his distributions and code are accessible through that forum.