Probably been discussed here before but I've been trying to figure a good color match to these. These had to be among the most widely used paints in WWII but it is very hard to find anything out about these. I know that they faded and manufacturers had their own formulas and batches could vary, but you gotta start somewhere.
Start with Olive Drab. I've been using Model Master paints for decades. They have MM1711 Olive Drab 34087 and MM2050 Olive Drab ANA 613, same paints? Then they add to that their versions of Faded and such. The period standard for USAAF aircraft paint was ANA.