We know Lucas has a habit of making a movie, then changing it every time he re-releases it. (If you're not clear what I'm looking for, Google "Han Shot First.")

Does he do this with only Star Wars movies, or does he do it with other properties? Has he retconned American Graffiti or any other movies he's directed? And has he managed to do anything like that with the Indiana Jones movies, which he created the stories and characters for, but which Spielberg directed?

Just how far into other movies has his habit to retcon reached?

(I know American Graffiti is not SF&F, but most of Lucas' movies are and he is a significant figure in SF&F. While I'm addressing more SF&F, keeping an awareness of his other movies is important as well, since it helps indicate trends and habits.)