Just to add to the confusion, I have an original 50th Anniversary book published by Ford Motor Company. In it there are color photographs (taken in '52). On page 48 there is a photo of both orange (what I've always called Ford Red) and green Flatheads. The caption reads "An aptly-named storage area at Atlanta is the "engine forest." The green ones are commercial truck motors and the orange ones are passenger car engines from the Rouge and Cleveland." Draw your own conclusions... According to the book, by '52 all car engines were orange and all commercial truck engines were green. In the photo the green appears to be lighter than the green used in '39 to '41Ford and darker than the green used on '49 to '53 Mercury and '49 to '51 Lincoln Flatheads...