Good points, pumpers, glennk419 and olneyrails.
The PN&NY connected with the North Penn at Erie Ave. It was the line that (looking N) split off the NP just before the Erie Ave bridge, curved around the roundhouse over towards 2nd St. and then paralleled the west side of 2nd for about a half mile. 2nd Street went up a ramp to meet Rising Sun, and the PN&NY continued on it's own r-o-w under that intersection.
2nd St 'disappeared' between Rising Sun, which runs diagonally, and Wyoming Ave. Above Wyoming, the tracks were now on the East side of 2nd, and they then ducked under the Blvd., bridged Ashdale, Duncannon and Fisher before curving to the NE and crossing over Mascher and Tabor Rds, near the current Olney Station, and thence onto Cheltenham and Newtown on the current alignment.
The current track from Olney to Newtown Junction was added by the Reading to route all trains to RDG Terminal. I believe that was in 1893. It crossed over the NP btwn 6th and 7th sts. I know we're a bit far afield of the original question, but that's how these threads go sometimes, right?