A minor difference that I picked up last time I read the novel: In the book, Vito is shot outside his office on 9th Avenue. My guess is that Vito was shot in Hell's Kitchen---somewhere in the 40s or 50s. That's where Puzo grew up, so he was probably writing about the area from firsthand knowledge.

In the film he's shot on---and his office is located at---Mott Street in Little Italy (well, it used to be Little Italy, now not so much ).

For the non-New Yorkers here, 9th Avenue is on the West Side and runs from the West Village all the way uptown into Hell's Kitchen. Mott Street is in Little Italy on the Lower East Side. The neighborhoods aren't really in close proximity to each other.

I wonder why they changed the location? Perhaps shooting in Hell's Kitchen was too much of a hassle? Or maybe Coppola just thought the Little Italy location was more romantic or exotic?