Those boxcars are privately owned, and are/were used for storage by the owner of that building. The track curved away from the Main Line right after those boxcars, past a small area people parked their cars, past a gate, and over the road to a customer formerly serviced by LIRR and NYAR - Chesler Plywood. One of the more difficult customers to service as there was always some type of roadblock to getting back there and never enough time to clear it. The other issue was the switch was protected by an electric lock, so by rule a train could clear the main there, but it was an older style of electric lock and would never clear the operator's board at Nassau, which would cause them to have to issue a train order. No one wanted to do this, so it was always known that you can't clear up there. (Freeport team track was the same way.)
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