1. Have Ben and Elaine live in Spokane.
2. Have Elaine go to school at U-Dub.
3. Instead of at the Taft Hotel, have Ben and Mrs. Robinson get together at The Davenport.
4. Keep the Simon and Garfunkel soundtrack.
5. Set Elaine's aborted wedding at the Cathedral of St. John the Evangelist and then have Ben and Elaine jump on an STA bus.
6. At that party early in the movie, instead of having that guy say "Plastics" to Ben, have him say "Assisted living."
OK, what did I forget?