He's a more detailed topo map using 5' intervals. The northern approach is at 950', and the old ravine floor where saline street used to be is approximately 830'. So the 120' height above ground holds, but not sure how much that changed when the parkway was build. Probably not more than a couple feet, which is within the margin of error anyhow due to 5' intervals. Doubt penndot did much more than grading.

topo map https://digital.library.pitt.edu/islandora/object/pitt%3A054e1935/viewer