Subsequent to my posting, I looked at the DPL site. My deduction: 473 got its diamond stack when shopped in Alamosa over the winter of 1961-62. I have no reason to doubt the 1962 date on the Rocky Club excursion. Also note that 473 lost its yard type pilot in that shopping. As I recall from some "old head" first-hand accounts, 473 was used as a switch engine in Durango during 1961. That probably accounts for a scarcity of 1961 photos of the 473, as I don't believe it was on the road much that year. At that time there was still only one train to Silverton. Two sections began running in 1963.