Cannot Delete Enterprise Custom Outline Codes

I have deleted all of the projects from Project Center on our PS 2003 server. I have dleted all of the lookup tables for all of the Enterprise Custome Project Outline Codes and when I try to delete them in the organizer I get the following

"You cannot delete a shared enterprise outline code whose lookup table is shared by another enterprise outline code. To delete first remove the shares."

I have revised a few of these in an attempt to start using them. When I go back and remove the renaming and delete all the lookup tabe data, these codes still show up as fields when trying to publish. Using SP2 version. Any help is appreciated. I'm stumped.