Well, see, that's why they gave up on the project. They could never completely remove the original music. If I recall; there was always the original score bleeding into their replacement music. And I can concur, as I wanted to change up music cues; if for anything so that the transitions would be smoother.
So I had to shift gears and re-think some things in my edit. And the big idea that I feel may have saved this edit was the fact that for the most part, I cut to black between classic and prequel footage. And like you saw before; I had some opening titles for the prequel sequences that was inspired by Pulp Fiction. (The Gold Watch)
Long story, short; no one has been able to change out scores in the Star Wars movies that I know of... I have however, added cues where there wasn't any where I felt it would add to scenes. For example, I added another instance of the Skywalker theme when Luke is eating with Owen and Beru; and he mentions Obi-Wan Kenobi. Also added some music when the droids are first in the desert. So, yeah, I made subtle music additions, and like I said before, I added grain reduction to much of Ep. 4 to match them up better to the prequels; oh and I reframed a couple of shots; but they are very subtle changes. Usually it was a wide shot that I felt should have been tighter.
I guess that's what some of my clips could be. I'll try and find some of these nice little moments.