Frisco passenger train at St. Louis coach yard (date unknown).
The Frisco Archive believes this is the Frisco’s and Katy’s Texas Special in the St. Louis coach yard looking east, with the Frisco’s own Meteor consist on the right. The first car is a Katy baggage car in solid red, thus dating the photo very late, perhaps 1958. The next car is the Frisco’s only streamlined full diner, which would be set out in Springfield in the wee hours. A couch/lounge/buffet car originally led the consist, but it has been dropped by this date.
Thanks to Ken McElreath for identification.