Contact the Purchasing Agent, Jamaica Station.
Question: Where are you going to put them?
The rail road will likely not allow them to remain on company property. Furthermore, you will probably get them in stripped condition. There may be fibers and chemicals on the cars that the state will demand you pay to have removed. You might get a cab sectioned from a car, if you happen to hit them on a good day, but my guess is, unless you are a bona-fide museum or preservation organization, they will rather have them hauled off and cut up in Mexico, for whatever established price the contract states.
Good luck, and let us know what ensues. I will be very interested.