From 'Pennsylvania Railroad Facilities Vol. 2': "Since March 11, 1936, both Perth Amboy Junction (Rahway) and South Amboy engaged in the practice of changing motive power for those locomotive-drawn PRR New York & Long Branch trains. Before the 1967 Aldene Plan, usually PRR rush hour trains changed locomotives at Rahway so they wouldn't block CNJ New York & Long Branch trains at South Amboy. Non-rush hour trains usually made the change at South Amboy."

Anyone know why the engine change was here instead of South Amboy? Found a clip on youtube with an engine change here or near here with GG1's and PRR sharks. Wonder if the catenary was being maintained south of here?

The location is indeed Rahway, but this interesting photo shows an engine change with a NY&LB train on the Perth Amboy & Woodbridge branch. 4864 is just about to couple up to this eastbound train, which will then proceed up the incline to the main line and past "Union" tower.