I've been spending a great deal of time reading old railroad journals lately.
It is amazing the variety of designs that existed, even within a short time period on a given major railroad.
The Master Car Builders all had their own ideas and creating "standards" for the simplest detail parts involved long, drawn out hard fought discussions. Every external feature of a common box car was different.....roof, running boards, ends, dead woods, brake gear, draft gear, trucks, underframing, bolsters, doors, sheathing, hardware, length, width, height, and on and on.
Interchange was a nightmare as the MCB members had to deal with carrying hundreds of different styles of repair parts for couplers, knuckles, draft gear components, journals, brasses, brake system components, etc., to fix foreign road cars.
If ONE prototype car was absolutely modeled down to the last bolt the modelers of that road would complain that the wrong class (or even lot number) was chosen.
How we molders have changed when we were grateful for Kar-Line and Bev-Bel for decorating Athearn and MDC 40' box cars in different road names, paint schemes and road numbers than what Irv and Clarence offered over and over!!!!
Charlie Vlk