Fixing bracing of Ovation guitars

So... the bracing in my best friend's girlfriends guitar has broken to changes in humidity here in the desert (it makes a bad buzzing noise when the guitar vibrates at certain frequencies). They have been very kind to me so I'd like to see what I can do to fix it (my friend is a pretty handy person himself). The problem, is, how does one fix bracing that is rattling and how does one take the top off of those darn ovations without doing any damage?