Has anyone contacted any of the theaters directly? I live near the only Oregon showing, but it's a Regal, and I don't think they'd know jack shit. Cinerama is a different story, however. They seem like they'd be more knowledgeable.
EDIT: I found a forum where someone got the running times from the films. This is what they were given:
Star Wars (2h 1m)
Empire (2h 4m)
Jedi (2h 14m)
http://www.film-tech.com/ubb/f8/t007339.html
If this is true, then you will notice that those are the theatrical run times.