[Mailman-Users] Mapping back from pipermail HTML to a specific message in the raw archive?

[Skip Montanaro]

I have a list of spam HTML messages in pipermail archives. I need to clear
out their content (no great problem there), but I also want to clean the
corresponding messages in the raw mbox file (zap subject, message body,
etc, but leave a placeholder message so future archive regeneration doesn't
mess up article numbers). Looking at one of these messages (HTML source), I
see nothing like a message id which would allow me to unambiguously
identify the corresponding raw message. Does something exist? If not, what
heuristics have people developed to perform this mapping?

Thanks,

Skip Montanaro