Hal 9000 said:
If I recall correctly, Sir Ridley helped remove the timecode as well. It was some advanced, painstaking effort and far from automatic.
That’s correct. SirRidley did most of the work on the Leia scene timecode and I just tackled one complicated timecode shot in that scene. It’s really painstaking, and this page details how I did it with moving objects in the frame:
There might be better technology now which can better automate the process.