You do know there was a very valid technical reason for the mono mix, right?

Nobody in 1977 knew if Dolby stereo was a flash in the pan or here to stay.

See any movies in Sound 360 lately?

Comparing the mono mix to the SE changes is mind boggling. There are many films that have different sound mixes. It's just that Star Wars' mixes has been documented in excruciating detail.

I watched Krull on DVD recently, and noticed a line was added when Liam Neeson's character dies in the stereo mix. It wasn't in the 5.1 mix, which I presume was derived from the 70mm.