Olive Drab is a descendant once removed from PC10 and Olive Drab is a greeny/brown colour. If we didnt have the moniker "Olive Drab" to describe the colour it would be alternatively described as Green or Brown.
I believe it was the cellulose coatings over the PC10 that gave a yellowish tint to the aircraft and made the newer aircraft ( or still shiny ) ones appear greener. As the outer covering wore, more of the PC10 showed through and it appeared browner.
Another thing to remember is that mass production back then was not Deming like. It was still predominantly a craftsmen's world and bucket chemistry ruled. PC10 mixes despite having an "official" recipe would have run the gamut of "She'll be right mate", "we are knocking off in 20 minutes" and "Hurry up Joe, it's smoko".
Factories would also have used what is there. A good example of this is in WWII when the Boomerangs came out painted in Light Green rather than Foilage Green for a period, for no other reason other then CAC wanted to use up their Light Green paint stocks. This is despite the RAAF having drawn up official camouflage patterns for aircraft in the three theatres around the Home Front and South Pacific.
Plenty of variety and tonal shades there to choose from, and all with the bounds of believeability and arguability.
cam
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