A big problem with the PRR 25 hZ was the PRR used as much of the 25 hZ for every electrical need. Example, many years ago when in BAL Penn station I could see the lights dim as trains accelerated northbound out of the station. Now how much off CAT equipment has been converted to 60 I have no idea. Maybe all?
It might be easiest although not the most important would be WAS to Perry. North of Perry the 25 hZ will be needed for the rest of the PRR tracks. Any specific 25 hZ equipment might be transferred there if needed. We have to remember that Amtrak is going to need more power for longer Regionals and more AX-2s.