Ted,
I think the purpose of this here discussion is the Silverton Train Set as it was during the 1960's. Mike was looking for information about the current whereabouts of Coach 320 then it turned into the discussion of the trucks for the New Steel Coaches and the Rider Gon's built during the early - mid 1960's.
For the most part, the Ex-San Juan Long RPO's gave up their 5 foot cast Steel Trucks with Outside Roller Bearings and inside hung brakes to the first (6) Steel Coaches.
When the D&RGW found the coaches 306 and 320 too worn out in the 1967-68 years, they sold off the bodies but kept the trucks for other new equipment they were building at the time.
We were just trying to figure out what equipment got what type of trucks, for this time period.
Kevin Cook