Thanks, Earl. I wondered how long before someone realized another historic car was 'modified' for revenue service. There were only 20 of these cars converted in the 50's from the Std gauge 66000 series boxcars. The Grande converted six of the cars originally to the now familiar D&S rider gons. The D&S has converted the remaining cars of this class to additional rider gons. There are no more to be had. The Grande and later the D&S kept the basic body configuration complete with the horizontal side planks and the z-bracing.
The C&TS received two of these cars, the 9613 and the 9615. They were eventually converted with minimal changes to 40 foot rider gons by the FOCTS in 1997 (according to the roster list on the FOCTS website) ,see Rich Muth's excellent photo elsewhere in this thread. This car has now basically been butchered down to the frame and will look nothing like the original car. It was used as a narrow gauge car and should not just be considered an old standard gauge car. Hopefully the other 9600 series gon will not suffer the same fate.
As Earl said, there is a stack of std gauge flats in Antonito that could have been used for this purpose, although getting them ready for use would have been difficult to get done before this opening day. I heard that there was concern for how much the top of the car was bowed out, but histerical pictures show some of these cars were bowed out at the top rail way back when. It is going to have side skirting to make it blend into the rest of the train. Nice.
So now what? It is gone I guess.