It seems that Republic started painting the cockpits grey at the factory in 1952 or '53. Before that they were the interior green. However, early airplanes that were sent through maintenance depot inspections seem to have had their interiors redone in the grey before being acquired by the NATO nations. At least that is what I can figure out from the research I've been doing. It isn't a hard fix in my case but another example of finding out new things almost too late to fix my mistakes.
