Not really a preservation or restoration, but more of a remix, but I just completed my 5.1 edit that imports the most notable changes make to the mono-mix. It includes Beru, several other alternate lines, sound effects, etc. Most come directly from the mono mix, but I’ve also used the 2011 BR to fill in to expand the mono to full surround. I’ve used the 93 ANH mix as the base. I also replaced the Fox Fanfare with the TESB one (I’ve never understood why they have never updated the music after rerecording it for TESB, not even for the SE). I’m glad I did most of the work in stereo first. Doing it in 5.1 was actually easier. I had to cheat in a few cases and resort to using the 2011 5.1 surround tracks instead of the L/R tracks due to traces of the original dialog. But the 93 mix (at least as we have it as a matrixed stereo track) has a lot of cross talk so I had to recreate that and the two little tricks end up sounding very natural. I still have to listen to the mix to see if it is final or if it needs work, but I have all the edits in place.
As a side benefit, I now have what I feel is an accurate LFE for the 93 mix. With some tweaking it should work for the 77 and 85 audio as well. But I will need to do that for TESB and ROTJ as well. That and a few other tweaks means the 5.1 mixes I’m working on won’t be just decoded Dolby Stereo. For the original theatrical audio mixes it will be close to the 70 mm 4.2 audio (modern equipment doesn’t really allow for 2 LFE tracks). For the 93 mixes, I am going to leave the surround as the ProLogic II stereo surround. It is not identical to the 97 SE, but very similar.
I also need to redo my BR ANH edit and finally get to TESB and ROTJ. I think I have a new approach that gets closer than my previous one. My GOUT color correction is, I think, final. The audio is almost final (LFE and tweaking the sync left). The 97 SE needs some tweaking to match my GOUT color correction. The only thing I need to do on the audio is pull the LFE track from Althor1138’s LD AC3 track. I think the end of this project is in sight.