World War I soldier driving a U.S. Army Medical Department ambulance at Camp Lewis, WA, Sept. 5, 1918. Signs on side of ambulance: Medical Department U.S.A.; Gift of California "Red Men"

it's a Garford.

The "Gift of California Red Men" refers to a small mens organization that originated in revolt to the taxes from the British on tea, and dressed in Native American garb, and held the Boston Tea Party!

"The order itself claims direct descent from the Sons of Liberty, noting that the Sons participated in the Boston Tea Party dressed as Native Americans. Thus, they continue to dress as Native Americans and are organized into tribes and such." https://en.wikipedia.org/wiki/Improved_Order_of_Red_Men

http://collections.washingtonhistory.org/details.aspx?id=112503