How to process a Zipped, Base64 encoded email body

People,

I get DMARC summaries emailed to me regularly, but, annoyingly - because 
it is a small amount of information anyway - the body of the email is 
Zipped and Base64 encoded . .

Before I try to work out how to process these mails so that they end up 
with a plan text email body, is there existing information about how to 
do this so I don't waste a lot of time producing something that some 
more clued-up person has already done more nicely? - I imagine that 
someone has already had to deal with this sort of situation . .

Thanks,

Phil.
-- 
Philip Rhoades

PO Box 896
Cowra  NSW  2794
Australia
E-mail:  [email protected]