There is some to be seen from I81 but if you don't know where your looking, and just to be safe, pull over to gander.
Not much can be viewed now. However once the leaves are gone completely in a month, you can see the ROW and the sloping that was done with the excavation of I81. The ROW is, more or less, slightly (and I mean very slightly) used by I81. Just after the Pine Grove exit (Exit 100) heading North, there's a bridge that takes 81 over Oak Grove Road. Immediately after the bridge, there's one of those 'Emergency/Authorized Vehicles Only' turn arounds. This turn around sits on the former S&S ROW. Have a look at the map link:
https://maps.google.com/maps?q=40.55224 ... 1&t=h&z=18 You can somewhat see the ROW on both sides of the Interstate, eastward to Pine Grove, westward to Gold Mine. Hopefully this helps everyone out a bit.