Hello Nate !
You mis-read in error, Ben's posting and photos with captions. Ben's Captions are are TOP of each photo they describe.
The reference you mention about Ben's caption.... "This is the West Side of Manhattan....." in that caption Ben refers ONLY to the NY Central Freight station tracks and platforms in the PHOTO DIRECTLY UNDER THAT CAPTION
That caption DOES NOT refer to the photo ABOVE it with the EL and the Composite Cars in it - that caption which I already corrected to Ben as NOT being the THIRD Avenue EL --in my just previous posting made a short time before your own posting to Ben !
Go BACK to Ben's original posting with its 5 photos (and the Lackawanna Loco pulling the R-46 cars) and carefully scroll down and view the photos AND captions -- you will see your "West Side" error ! ALSO note my posting to Ben giving CORRECTIONS info on that and another photo
Regards - Joe F