The 1501 and 1502, rebuilt from 1801 and 1802, were used on the Firefly. The Frisco Firefly cars as best as I can tell were the only Frisco Cars to have full-width or car-body diaphrams. Pictures of these cars show porthole windows on the rear. Since these cars had a rear vestibule and lavatories at the end of the car, it would appear that these windows were more stylish than functional.
Karl, I don't know a lot of the history of the Frisco. What I do know is that on four occasions in the early 60's I road the Frisco from Kansas City to Miami Oklahoma and on all occasions we chose to ride in the Grill/lounge car at the end of the train with the observation platform I could stand on and watch the countryside fall away from me. Would you be at all familiar with these cars? I have perused the internet on many occasions and have yet to find a car that would pass for what I remember. They were about half booths in the front and a grill w/short order cook, stools at the counter and tables across from the counter(?) (the cook remembered our family every time we got aboard) in the back half of the car. I wonder if it was one of the business cars retrofitted. Any information would be greatly appreciated.
You rode in one of the 1600 class Buffet cars. None had a rear "observation" platform, only the normal vestibule at each end. I'll post the car diagrams. The interior of each was slightly different. I remember them from trains 107 and 108, the Sunnyland