I'm not an engineer, but we know how far down range the Saturn V stages impacted when launched from Cape Canaveral, and we know these numbers are accurate since parts have been recovered from those locations. So . . . just plot from Vandenberg over the continental United States to see where, generally, they'd land. Or am I missing something?
Yes, from my perspective, you're missing how you know "how far downrange the Saturn V stages impacted" You might know it, but I don't. And I don't have a clue where to begin going through the massive NASA webpages to find first-source material.
We all know they did, but I have absolutely no idea where to begin combing through the massive number of NASA webpages to find first-source information. My initial search led me to the Technical Documents server, and two hours later I gave up because nothing germane to what I was looking for came up.
A second-level or third-level citation is okay for personal purposes, but in the academic world, first-level only. There's too much information coming up, and none of it is specific. And even if it did come up, I don't have the trigonometry or calculus skills or education to figure out what the heck to do with it.