Back to RcT's original question, here's a post from Pat in Santa Cruz on the Commercial Vehicles thread:
Vince Falter has some nice US military images, including a station wagon.
There are also good images on the Commercial Vehicles thread of "A's" in the 1930 Brazilian revolution, and mounted with a Maxim machine gun in South Africa.
As previously stated, there are many images of GAZ vehicles "on duty" for the Red Army in WWII.