In July 26th 2007 Adult Swim had a special midnight airing of sneak peek of the Simpsons movie, so far only the one promo has been found of this and rather than footage of from the actually Simpsons movie being used Aqua Teen Hunger Force characters dressed as the Simpsons cast are seen reenacting scenes from the Simpsons Movie trailer, the voice over said "A sneak peek a couple of weeks in the making" as well as that the sneak peek was "Adult Swim Style".
Very little information on this has been found online & the only evidence is the promo and an Adult swim schedule archive noting July 26th had "The Simpsons Movie Sneak Peek". Look through the Adult Swim Archive it must have only aired once on Adult Swim.
Aqua Teen Hunger Force Simpsons movie promo
Promo for the event.