Check the Listener/Project.php file, I have no access to sftp atm, but I remember doing the same, customizing the php code to control the tab.
I limited it myself to super admins only for the site we were using it on. You probably want to check against the unique user group id user_group_id
that said, i moved away from using it and am using a second forum for project management which has it's features slightly customized, and is using tags to organize it's content. Simpler, and to be honest, more effective. </offtopic>