KJ, you're right!!!! I never noticed that myself, but you're absolutely right. Well, maybe it's because we're only looking at the port side of the fusilage in that trench run scene, and the full studio propis being shot from the starboard side? Maybe the ship has a different stripe on each side <<Shrug>>. I seem to remember someone, either Lucas, or someone at ILM making a point about the colours being broken up because you're looking at where panels have been replaced and repaired, without time or energy to repaint the ships markings. But, damn, I've watched these things since I was three and never noticed that!
The Death Star plans...yeah, I guess I've just gotten so used to that one that it doesn't even occur to me anymore

For a while there I thought maybe you could make the argument that what the rebels had were prototype plans for the DS. But then AotC killed that idea (though, notice they DID use an idea from the development of DS2, which you can see in the Return of the Jedi sketchbook....namely the DS having those little pod things projecting off of the surface on pylons...kinda cool to see).

What about the Falcon's "fuzzy dice"? They're there in the shot where Chewie is getting the ship ready for departure from Mos Eisley, and NEVER sho up again.