I supposed one can make a R-rated musical out of "Music Man" (or anything) if they wanted. They did something like that when Julie Andrews' film-within-a-film of "SOB" had her go topless. Then again, there are kids in the cast of "Music Man", so I think it's not well-suited for what is basically a family musical. They can take out the Native American part though, as something else could easily be substituted for it. Hopefully Grecian urns won't offend Turkish patrons though.
