IF your copy of Spamassassin has allow_user_rules turned on, you can cut and paste the rules from those .cf files into each site's spamassassin user_prefs. It is probably not turned on, however:
"This setting allows users to create rules (and only rules) in their user_prefs files for use with spamd. It defaults to off, because this could be a severe security hole. It may be possible for users to gain root level access if spamd is run as root. It is NOT a good idea, unless you have some other way of ensuring that users' tests are safe. Don't use this unless you are certain you know what you are doing. Furthermore, this option causes spamassassin to recompile all the tests each time it processes a message for a user with a rule in his/her user_prefs file, which could have a significant effect on server load. It is not recommended."
I'm sure you already know that someone with root access can just put those .cf files in etc/mail/spamassassin and they will become active when spamassassin is restarted.