PRR elevated the tracks thru Newark circa 1904; the elevated South St station replaced the surface-level stations at Emmett St and Chestnut St.
South St is in the 5/74 public timetable; it's not in the 4/76.
Stand on the platform next to track 1 at Newark now-- looking SW, track 1 is straight all the way to the Hunter curve. That shows you where Newark Market St station was until they demolished it circa 1935: on that line on the SW side of Market St. Four tracks NE from the Hunter curve pinched down to three just SW of the station; three tracks thru the station, with platforms on the outside tracks, then two tracks on the swing bridge across the river.
Circa 1935 they built the present tracks 3-4-5 alongside the old station, moved the trains over there, then demolished the old station and finished the present layout that opened in 1937.