In the Book
In the Movie
Sal lives in New Jersey.
He lives in Ozone Park in Queens.
Dean badly injures his thumb when attempting to hit Mary-Lou. He keeps it heavily wrapped.
He never hurts his thumb.
Sal and Dean share a car ride with a homosexual salesman and a young couple. Dean tries to get money from the "fag" in many ways. He doesn't have sex with him.
The "fag" comes to Sal and Dean's room and Sal watches through the bathroom door as Dean forcefully sodomizes the man. He doesn't give him any money.
Dean has another relationship with Inez who he impregnates. He plans to marry her, but leaves her to go back to Camile.
She doesn't appear.
Sal and Stan Shephard plan to go to Mexico. Dean hears about the plan and gets a car and they all drive there together.
Sal and Dean go to Mexico alone.