I know the has an interesting history when it ran it ran between 168th St and the World Trade Center until December 10 1988. That was when the was extended and ran along the (K)'s former route. I don't see a future for the train when there are already 4 services running down the uptown Eighth Avenue Line. The , (, , and the already took the room for the . The would need a whole new tunnel.
Here's another photo of the vandalized.