After publishing this post, I received the following message:
"Thanks for the photos. When I was a kid, we would drive-at least once, if not twice a year to Oklahoma from California. My parents never let on why we could not stop and go to bathrooms at service stations...or why we could never stop and get a hamburger. We thought my Dad just would not stop because he was always trying to break his record…and that was on was Route 66 (which wasn't much of a highway, mostly 2 lanes). It was only as a young adult that I understood. I found a micro fiche of the Green book when I was studying at UC Berkeley.
I will share with my cousins...who remember those trips as well."