I found a copy of a SRY TT that Marvin Black copied andĀ sent me probably early 2000's.
It does not mention the year but as I recall Marvin stated it was in the 1940's
It has a few codes:
I can probably scan it into a PDF if anyone is interested. A few codes include: G Coaling stationĀ (chute bin,platform tipple) H stock pen K turntable P hospital at that location R engines are coaled from cars at the location Y "Y" track at location