Trains on this day in the past:

[Charlie B]

Stephen, that is an S-1 it is the non turbo version of the 539. the Blunt trucks are on the S-1 and S-2 while the S-3 (non turbo 539) and S-4 have AAR trucks. The S-1 and S-3 are shorter and have some differences in the doors compared to the S-2/S-4
Charlie