The New York Times of October 19, 1963 reported that FDNY planned to swap frequencies with the Elizabeth, New Jersey Fire Department contingent on FCC approval. FDNY would receive the 153.77 frequency in exchange for giving up the [unused?] 453.15 frequency which then became the EFD's. An amount of cash, $42,000 was appropriated to Elizabeth to "buy modern communications equipment for Elizabeth's Fire Department."
153.77 was to become the Queens Mobile frequency which suggests that Brooklyn and Queens became separate after this. I guess FDNY needed one more VHF channel. An official reported "The transfer will improve the efficiency of the New York Fire Department's radio communications".