I'll try not to be so confusing
First, Look at N28PU: there are two profiles and one is bogus. The N28PU with c/n 75-3412 does not exist and should be de-linked from N2PP. The only N28PU should be with c/n 75-5736. That's where I moved my photos to. Mine are AC120299, 300, 301.
N2PP has two correct profiles. The bottom one, with c/n 75-5736 needs to be linked to N28PU. This aircraft was removed from flying status and is displayed at the Kalamazoo Aviation History Museum. The three photos with the top profile, AC115561, AC92283 and AC54414, should be moved to the bottom profile with c/n 75-5736 or else to N28PU, which is the actual number it was registered as when the photos were taken.
The confusion comes because when they retired the plane they still kept the old number painted on its side, N2PP, as an honor. Another plane painted identically and active took the number N2PP so as to keep the number active. So two planes actually wear the number N2PP, but the one in the museum has not worn it as an active airplane for over a decade. Do photographers may think it should be posted as N2PP as if that was its number when photographed.
It's sort of like the Air Force Museum honoring a plane no longer extant by painting and marking a preserved aircraft as the extinct bird. We post the plane as its actual s/n regardless of what is painted on it. The photos of the Stearman at AZO should really be posted at N28PU regardless of what the fuselage says.
Does that make sense?
Glenn