Found this on fee bay. It has a nice explanation of the progression of factory marking changes through the production runs. It also has a complete list of all the 8th and 9th air force P-47 unit codes, and all the colors used as identification by ETO and MTO P-47 squadrons. It also lays out the all the basic insignias with dimensions, as well as the invasion stripes. Very useful resource. I'm also ways on the lookout for more research material to add to my library.
