List archive removal requests

["Christopher P. Lindsey" <lindsey@xxxxxxxxxxx>]

Hi everyone,

   I have a non-MHonArc-specific question to ask.

   I recently opened my archives up to Google for indexing and have
   become inundated with requests to have messages removed from the
   archives.

   Usually they're from family members who don't want grandma's 
   email address published, but I received one today from a large
   organization that is apparently in hot water because of something
   that someone posted ten years ago about a tract of land in 
   Texas.  They now want me to remove all posts referencing their
   organization and the poster.

   What do all of you do?  And are any of you familiar with the
   legal requirements to remove messages?

   When people signed up for the lists they were told that their
   messages would be archived indefinitely and publicly.

   And even if I remove the message in question, their message is
   quoted in peoples' replies.  Do I have to delete the entire 
   thread including what other people have written because this
   guy's name might be in the email?  Even if I only strip out what
   he has written other people have incriminating information in
   their responses.

   And, of course, the other big problem is time...  If I have
   to go through 10 years of archives searching for mention of 
   this organization or the poster and then edit the emails and
   rebuild the archives it's going to be a huge timesink.

Thanks for any input,

Chris