Hey 13M,
With a few web searches, I turned up the following on Conway Yard in Pittsburgh, PA.
http://kc.pennsyrr.com/art/images/1958.jpeg
^ This is a artist's picture of the yard, circe 1950's. From what I can see, looks like any other railyard during the Pennsy area.
As you may know, the PRR merged with the NYC, hence PennCentral. Eventually, PennCentral joined four other Northeast RR's to form Conrail. Conrail now owns the yard today.
I, personally, couldn't find a map of the yard, or any detailed photos. I did find:
http://www.dementia.org/~patrick/images/Conwaybldg.jpg
^ The yard building, from 1995.
www.trainweb.org/ eastpenn/cleve.html
^ A site with some UP and Conrail freight locos at Conway.
Hope this helps! :thumb: