To be specific 41, the EDNA, Caboose 0402, and Galloping Goose #3 are the only RGS equipment at Knott's.
The 340, Chama, Durango, 310, 325, 326, 9519, 5576, 464, and the 4 freight cars that left the farm were all Rio Grande.
The San Juan was discontinued before Walter Knott started buying equipment.(starting with 41, and 0402 in August 51) In one of Colorado Rail Annuals there was a list of cars for sale by the Rio Grande, in that list was two Parlor cars. IE the Chama, and Durango. Walter bought them fare and square from the Grande, who didn't need them anymore. Along with 325, and 326. 310 and C-19 340 came later in march of 52.
Knott ended up with Colorado NG because alot of it was for sale, and cheap.
The Chama, and Durango came to Knott's just as they were on the Grande. In the mid 50s Walter wanted a combine, so he had the shop crew convert the Chama into one.(I guess it was cheaper than buying one from the Grande, which had them for sale) When it emerged from the shop it was renamed the Calico(later also re-numbered 351). In honer of Walters passion for the old Calico Ghost town.(Same reason why our RR is the Ghost town & Calico RR, and why we have the Calico mine ride, and Calico saloon)
In 2008 the Chama name was placed back upon the car.