I'm working around the model of the second version of Hotchkiss-Ighorsky armored car, also known as "Lotta". And have only one picture, where I may get color from.
Looks too pale green to me - sampling from the images of Wayne's models I get 80:72:51 , 96:99:68 , 129:108:77 , 117:118:110 (all rgb in decimal) - any one of those colours would be an acceptable Feldgrau (I think).