This was just another standard D&RGW 6500 series flat until the D&S converted it into its current appearance. Seems to be serving them really well for their needs to haul equipment throughout the line. Don't exactly know what year the modifications were made though. The current configuration is much easier than having to haul around the large timber ramps the D&RGW used originally to load automobiles on the 6500 flats.
I especially applaud David for wanting to model this car in particular, gets too much hate from all the rivet counters!