After they filmed it, the studio saw the daily rush of the scene & deemed it too bloody for the times (remember, this was the early '70's), so FFC left it out.
One of the stills of that scene in Lebo's book shows Fab covered with what looks like 2 gallons of Caro syrup. It's a wonder he didn't drown.

On Part 1, there were days when the actors would literally get the script the morning of the day's shoot. Which drove everybody nuts. Brando had his lines hidden taped all over the place (on his desk,on other actors,etc)
Another still from Lebo's book shows Robert Duvall with a cardboard strapped to his chest containing Brando's lines. Lebo tells that in the scene between Luca and Vito in Vito's office on the day of the wedding, Lenny Montana scotch-taped a piece of paper saying "F**k you!' to his tongue--and stuck it out at Brando during the filming.

Do you have Lebo's book? It's the bible.