<<<Does anyone know of a publication or have information on all of the PC (PRR heritage) heavyweight passenger and baggage cars relegated to MW service ? >>>
When Brannibar's PC roster project was rolling along smoothly it was supposed to be in Volume 9. Since it has died, I don't know what the future is for this body of material.
I have some CR roster info if you ask me for specific #'s I can look them up if they lasted into 1976.