There is a way to preserve the 1979 version and the 1983 T.V. version using the Directors Cut DVD, 1979 widescreen Laserdisc, and the 1983 pan & scan laserdisc version.
Using a NLE software, import the 1979 footage and soundtrack from the 79-widescreen laser. Then take the video only from the Directors Cut DVD and overlay it on top of the 79-laserdisc footage where possible. Parts of the Klingon battle are missing from the DVD, so you will need to mix footage. Use filters to balance the look where you mix laserdisc and DVD footage. For the Vulcan and San Francisco tram station shots, just use the cut footage in the DVD extras section. For the lounge scene, I just use the laserdisc for the shots we see the window. If you just use the laserdisc soundtrack and as much footage as you can from the DVD without the added effects, you should have a kewl looking Star Trek The Motion Picture Preservation.
Now for another version (The Longer Extended Cut),
Using a NLE software (such as Abobe Premiere), import the 1983 pan & scan laserdisc version with Soundtrack. Then take the video only from the Directors Cut DVD and overlay it on top of the 1983 pan & scan laserdisc footage. Use all the cut shots from the DVD's extras, and use shots from the 79-widescreen laserdisc where you need to. If you do this, you should have the extended version of the film in WIDESCREEN format. That is something that has never been available.
Now I am returning to my work on a re-edit of the film (much like my DUNE re-edit), so I'll leave the preservation to other fans.
FanFiltration
(THX-1138)