Flying Tigers' Colors

Most US Aicraft came out of the factory cammoflaged with Olive Drab upper surfaces and Neutral Grey undersides (medium gray?). If there is a two tone upper camoflage (brown /green for instance) than, it is likely just the factory scheme with some RAF brown sprayed on top (some version of RAF Earth I imagine). Hope that helps.

For the AVG birds, the upper surfaces on the P-40Bs were British Dark Earth and British Dark Green, with undersurfaces a shade of gray somewhat lighter than the US neutral gray.

If you're building an AVG "E" model, the pics I've seen had them as OD over neutral gray, though some may have been the Dark Green/Dark Earth scheme. I've not seen any pics of those, but several folks have said they've seen that.

The debate over scale effect is an old one with opinions either way. To my eye, lightening up colors a bit on smaller aircraft does appear to look better, but if you use various pre-shading and weathering techniques to vary the  colors, it'll accomplish the same thing. 

"Very small scale".....leaves a lot of room for interpretation....if tiny, I would say....use an olive drab upper and light grey lower.....but lighten the green......the smaller the subject....the darker the paint will look.

For help......go to the 'Aircraft' topics and click on anything mentioning a 'giant penny'

Nam