Black Hills Central Gondolas

I was looking through some old slides today an came across some taken at the Black Hills Central in South Dakota around 1960. One of the slides shows White Pass & Yukon #69 coupled to a train of 5 passenger cars made from converted D&RGW high side gondolas.
If I have the history of these cars right, they were built by the D&RGW for use at the 1948-49 Chicago Railroad Fair, the Rio Grande built some for their narrow gauge train as well as some for the Colorado & Southern (Burlington Route) to pull behind C&S #9. Following the fair, the C&S equipment, including the converted D&RGW gondolas made their way to South Dakaota, while the gondolas used by the D&RGW became bleachers in Alamosa. Eventually, three of the cars converted for the C&S made their way back to Colorado and are now on the Georgetown Loop as cars #5, 7 & 9.
My qustion i this, how many cars did the D&RGW make for the C&S? Was it 5? If so, where did the other two go?
Kind of odd that all of this equipment, including WP&Y 69 is now in Colorado.
Jason Midyette