My sister's high school used "You're the One That I Want", completely cut the character of Marty, gave Rizzo a cousin, gave "Freddy, My Love" to Jan, and made Danny and Sandy black. They also had a screen and showed the beach scene from the movie and the "Grease" opening song. They may have made more changes but I can't remember.
They also gave lines to Toto in "Wizard of Oz", had two Wicked Witches of the West, and added "Lullaby to Broadway" for the General to sing in "Guys and Dolls".
I couldn't even tell you what they did to "The Music Man" since I didn't see it.
"All our dreams can come true -- if we have the courage to pursue them." -- Walt Disney
We must have different Gods. My God said "do to others what you would have them do to you". Your God seems to have said "My Way or the Highway".