Please find below a link to an interesting film made by the New York City Board of Transportation in 1949. The film is interesting in that it presents the actual sounds of old equipment that have passed away from the scene many decades ago. The film was not edited correctly, because it shows a train starting out as an IRT Lo-V but as it goes through the system it becomes a IND R 1-9. Despite these problems, you will see good shots of IRT equipment (Lo-V's) and the standard IND equipment as well. You will get to see, even though a few seconds, the iconic skyline of Manhattan through the girders of the Smith-9th Street station. You will get to see the new IND R-10's and the Euclid Avenue Station. For those 76 Street investigators, you will get to see for a few seconds the signal board at Euclid Avenue in 1949 about 7 minutes into the film. Perhaps there is some information there that is useful. So sit back and enjoy. It is interesting that no BMT equipment or 3rd Avenue El scenes are shown. It is important to remember, as it seems to me and I am no expert, the New York Board of Transportation was no fan of streetcars, elevated lines or innovative equipment such as articulated cars. This is my opinion only.