Since the OT is older than the PT, perhaps this could be reflected in the visuals? For instance, the crawl (disregarding the way things actually used to work, since I'm ignorant of that):
We accidentally start from the second reel of the movie, which stops when the projectionist realizes his mistake. The screen goes blank and there's some muffled cursing and bumping around. Then the crawl ends up upside down at first. When things are finally sorted out, it begins. The crawl slowly and very jerkily, um, crawls up the screen with a loud cranking sound to go with it (presumably from when the crawl was done originally, not because of the projectionist). The crawl progresses slower than the audio, so the theme plays and ends, either leaving the cranking as the only sound, or continuing with the audio from the first scene.
You could also have some very obvious and badly done reel changes throughout the movie, or having reels from completely different movies begin to play. A blank screen and the crashing/cursing sounds of the bumbling projectionist could then follow.