I can pass on some tidbits from the late aviation author Tom Doll. According to him and the recollections of VF-6’s Howard Packard and others, the early late 1941 to Spring, 1942, non-specular sea blue birds were significantly darker than later ones. This is likely because the Enterprise’s air group was painted homebrew style aboard ship per Halsey and Browning’s orders alone, so they were limited to what paint stocks they had aboard; Tom said they got close but not precisely there. This created a bit of a kerfluffle with the aviation forces ashore when this became known as sourcing replacement paints and specifying the proper shades at the factory and repair and repainting depots was, of course, important.
Tom told me that he spoke about this “home brew” darker non-specular blue grey with a number of pilots from Enterprise and other carriers apart from Howard Packard over the years. While time must inevitably fade memories, there seemed to be a general consensus that the Enterprise Air Group’s non-specular sea blue was somewhat darker, in general, as originally applied at sea. If memory serves, Howard Packard wasn’t aboard Enterprise during the Pearl Harbor attack (aboard Lexington?), so Tom always put great value in the fact that a pilot from another carrier noticed how much darker the Enterprise Air Group’s paintwork was. Howard Packard was an artist postwar, and had a keen eye for colors and hues, Tom always said. Take this however you will take it, accept it, reject it, whatever. I’m just passing on Tom’s conclusions from speaking with the men who were there. He told me once that the Planes of Fame Museum at Chino would receive much of his research after his passing, so presumably its there now, waiting to be catalogued and sorted.
Tom suggested that anyone painting a very early war Enterprise Air Group model should paint it slightly darker than whatever paint shade is in the bottle (assuming the paint in the bottle is correct!). This was because the real thing was painted that way, and because the fresher paint hadn’t had much time to fade and weather. Replacement planes sourced from ashore would likely have a non-specular blue grey that was lighter and more in line with the standard non-specular blue grey that we all know and love. By the time of Midway, if not the Doolittle Raid, most of the prewar birds had been replaced other than the TBDs so the regular 'ol non-specular sea blue would be the correct paint, and even the TBDs had likely been repainted or at least touched up.
I hope this helps,