For what it's worth, I have always heard the reinforced door called the "camel" door and the plain door called the "economy" door. I have no idea where the terms came from or whether they are truly accurate. Also, the "camel" door has more than the horizontal brace to distinguish it. The door is braced all around the perimeter and has a more substantial latch. I believe the runner is also different. Both kinds of cars remained until the end. You could see both kinds of doors on different boxcars in Chama and I assume you still can, though I haven't looked in years.