Pete, Thanks so much for your help on uploading photos. It worked as you can see.
I will start with a couple of photos of the second class car that I am modeling. Here is a train pulling several of the cars.
I took this photo of a car being painted at the railroad museum in Puebla, Mexico. Sorry about quality.
It turned out that this car is about the same length as a flat car except for the platform extensions. The wheel base is about right and it appears that it rides on arch bar trucks or something that looks pretty close. It almost looks like these were actually built on a freight car base but the floor is the same height as a regular passenger car. The sides come down so low that they almost hide the trucks.
I started with an Accucraft flat car.
The stake pockets and end beams were removed.
Parts of the end beams will be used later to make the draft gear.
A floor was made that sits on top of the flat car deck.
The car sides are built in 3 layers. The outside layers are made from Evergreen .060 thick grooved car siding. They split at the belt line which made it easy to cut out the windows. The belt line was made from strip styrene and glued to the top of the lower wall. The window section was then glued to the top of the belt line and window trim added. The outer wall was painted before continuing the construction.The second layer is a single piece of 3/32 Lexan glued to the inside of the wall with super glue gel. The inside of the walls will be finished with wood veneer. Here are the parts I have so far.