Okay, here, now, is where I am not sure what the proper protocol is in terms of communication. That is to say should I continue my conversation with the leprechauns here, or should I email . ...... them? I'll write here for now, until I hear otherwise.
I found my copy of "Pittsburgh, Then and Now" and if you go to the back, P. 325, you'll find a list of who owns the THEN pictures that were used. Most of them seem to come from two sources. if this were me I'd go to those two archives, with your book under your arm, and talk to the friendly folks at Reference, who will refer you to someone else, who will send you to some dusty office in the basement where someone will tell you that it is, "Okay to use the images if you give us credit", or will tell you, "Sure, for $20 a picture" or whatever. Go there assuming that you bring with you so much joy and enthusiasm about Waymakers that they will not be able to refuse you. Then get out your GPA unit and go crazy. eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeek