PRR RS3 Lettering

[Green_Elite_Cab]

This is just speculation on my part, but when they started talking merger with NYC some locomotives got large numbers when they where shopped, and they may have omitted the lettering in anticipation of the merger. It would have been pretty fast to remove a herald. I believe they started talking in late 64.
Charlie

As i understand it, the last PRR locomotives to get a full "Pennsylvania" on the sides were the E44 electrics. After that, it was Keystone emblems only. they arrived in 1960. While i have no doubt possible merger was the reason, i think i also heard somewhere that it was getting to expensive to maintain the lettering on the side, or something of that nature. the PRR was strapped for cash in those days.