Number 1042 is an Alco RSD-1 built in 1941 (builder #69425) for the U.S. Army, #8006 (nee CRIP RS1 749).  The Alaska Railroad purchased it in 1951.  They retired it in 1956.  It then went to the US Army #8006 and then to the Tennessee Valley Authority #48.  The above photo shows Engine #1042 at Healy, 1950-52

Photo courtesy of James Sava
Retired Alaska Railroad Trainmaster