In the Book
In the Movie
Sal lives with his Aunt in New York.
He lives with his mother.
Dean wants to learn to write from Chad King, but he tells him he should learn from Sal. Dean goes to Sal's aunt's house after only meeting Sal once and asks him to teach him to write.
Dean knows Sal well and just before he is going to leave to return to Denver, he comes to Sal's and asks him to show him how to write.
Doesn't happen.
After Dean asks Sal to teach him to write, Sal types a line about Dean being a Cowboy.
Carlo meets Dean after Sal has already met him.
Carlo is with Sal and Chad when they go to meet Dean.
Carlo, Sal and Dean all take separate photos in a booth. They cut the picture of Sal down the middle and Carlo and Dean each put a half in their wallets.
They take one picture all together and cut it down the middle of Sal's face. Sal keeps the half with Dean's face and Dean takes the other half and puts it in his book.