Most Star Wars Actors in a Non-Star Wars Film

Here’s an interesting bit of Star Wars trivia.

Q: Which non-Star Wars film featured the largest number of Star Wars actors?
A: Two films are tied with 17 actors each.

Looking at the actors listed for other films featuring Star Wars cast members, I found a curious entry: John Ratzenberger who played Cliff Clavin on Cheers. He was in a Star Wars film? Yup. He had a small role in The Empire Strikes Back.