ORIGINAL: G-Pete
Sometimes that is misleading, Airplanes in a Museum. Many times to keep the airplanes airworthy the whole set of rivets are exchanged. That means better (and flush) rivets will be used. Better to look at pictures back in time.
Good example is the Hellcat, hard to find a airworthy F6F with raised rivets on the fuselage. They had raised rivets on the fuse...