As noted on the original thread with the photo, I wonder how much if any of the gravel version highway 17 was the old toll road. If the Osterwald maps are correct, the Toll Road in the Coxo area was south of the creek, did not cross the railroad, and took a steeper more direct route up the draw to Cumbres. But I could find no sign of such a routing on Google satellite views, so who knows for sure...certainly not me.
On the other hand, around Cascade Trestle the toll road is very apparent, and provides a convenient trail from the railroad grade down to the base of Cascade trestle for photographers. And there appear to be traces of it paralleling the railroad to near Los Pinos phone booth.
JBWX