Hello Tom !
Per my long reply post to you ---these two photos will go with the story line text of my paragraphs below;
Here above is a (the TOP PHOTO) photo of the E. 133rd St Alley station being demolished in May of 1958. I have photos of the line being demolished at E.145th and 146th streets on Third Ave., in 1958.
Also attached, (LOWER PHOTO) an aerial photo of the CNJ's Freight "roundhouse" and surrounding freight yards and float bridges area - and the 3rd Ave El Bridge in background. The Bronx approach to the Third Avenue Auto bridge is at bottom right.
That freight barge photo (I have had a copy of one for years in my collection) is looking West from the pedestrian walkway on the west side of the 3rd Avenue Elevated IRT EL Harlem River Swing Bridge near the Manhattan shoreline side -- with the Bronx approach bridge for the 3rd Avenue Auto Roadway Bridge seen crossing behind the barge --- with the CNJ's Round Freight House at right immediately east of the Bronx roadway approach to the 3rd Ave. Bridge. Following that is the original (actually, 2nd generation) NY Central Railroad Swing bridge from 1898-1900 approx. -- and immediately behind and close parallel to it is the raised completed side one half span of the two span (2 tracks on each span-half) brand new NY Central Railroad LIFT BRIDGE. This view has to be in late 1954 up to thru mid 1955 and prior to the closing of the IRT 3rd Ave "Manhattan" EL and its swing Bridge by Friday May-13-1955 12:01 AM . Shortly thereafter, the EL's swing bridge was left fixed in OPEN position for any river traffic, until the bridge was taken apart and removed by Feb 1956.
I remember this area very well from my many rides over the 3rd Ave EL Bridge on trains back and forth, as well as even more trips in my fathers' 1950 big Mercury car over the 3rd Avenue auto Bridge to and from the Bronx. Around 1959 and years after, I walked thru those rail yards and took photos -- by that time the 3 years abandoned but intact (since May-12-1955) EL structure from the Harlem River Bronx waterline edge north to E.148th street on Third Avenue, was finally torn down between May 1958 and August 1958. It was kept up from that point - up thru the famed "alleyway" between E.133rd St and its double-decked alleyway EL Station there, thru E.143rd St "alleyway" Station - and to the E. 149th St Station, as a turn back for Bronx Line only SB EL trains into E. 149th St "terminal" station. SB trains on the local track discharged passengers, then went empty, southward to the alleyway portion starting at E.144th Street, and used it via a " Y " switching arrangement via a single track two-way center ramp at North end of E.143rd Street lower "locals" level station, to the upper level... 2 track express level, to turn trains around to get back to the north local track at E. 149th Street "terminal" station. Of course, in those daily 'non revenue move" 3 years, the 3 EL stations (143rd, 138th and 133rd Streets) in the alleyway were permanently closed and barricaded.
That switchback operation even lasted after 12-16-1956 when the wood EL cars (MUDC's and Q Types) were replaced by 6 car trains of IRT Steel original body Low-V Steinway Subway Cars - the first time Steinway Cars (or Low-V's) ran regularly on the 3rd Avenue EL line below E.149th Street towards the river (but without passengers as reverse-move-deadhead's). That structure, unlike the Manhattan portion, was built to handle steel cars.
Once the new Terminal Switch Tower was erected and completed over the former center express trackbed at the north end of E. 149th St Station, and all the new reverse moves signaling and wiring was installed along with the new X Crossover and 4 switches installed outside the north end of the E.149th St Station, by February 1958, allowing trains to enter and exit either of the 2 tracks at the E.149th St "terminal" station, and depart to the proper n/b local track, the EL cut off at E.148th Street and from that point south, to Harlem River Edge, was removed.
I saw an article (maybe saved it, have to check) with photos -about a guy who built a full HO Scale replicated version of the entire CNJ Roundhouse freight house and float bridges, including replicating that unique switch and crossover trackwork unique to that terminal complex !
PS: Jim P, we saw PLENTY of NYCRR electric boxcab loco and MU action at Woodlawn JCT and New Haven electric boxcab Locos and MU's in that area back in the 50's and even 60's !
regards - Joe F