Hi Frank,
In the book Pennsylvania Railroad Diesel Locomotive Pictorial Volume Five Fairbanks-Morse Locomotives by Paul K Withers from Withers Publications there is a history of the Erie-builts.
The official designation of the units was Alt.100.3 and Alt.200.3 but because they were assembled at the GE Erie Built plant the became know as the Erie-builts.
It would appear they were built to three orders and were first built as FF-3, FF-3s and FF-2. Later they were re-classified as FF-20, FP-3 (Later FP-20a) and FF20. The FP-3 (FP-20a) were the second order and were A-B-A consist to make up the 6,000 HP units the Pennsy thought to be the optimal locomotive size. The last order were paired A-A units for helper service. The Units 9472-A to 9479-A and 9472-B, 9474-B, 9476-B and 9478-B were the FP class and were fitted with steam generators. They were re-classified FF-20 between Oct 52 and Apr 53. By the end of 1963 all units had been removed from the roster and traded to GE on U25Bs. In the book there is a photo of a pair with 9476 leading on train 208 the "Ohioan" and then there is another photo of another A-A pair running a train of four P70 variant coaches on a day train in Cleveland. Most appear to have spent their life in the Buckeye and Pittsburgh regions.
I do have a few B Units that were made from cut up A Units shells and cast by Raintree Models in the US. I recently bought a Pair on the bay complete with trainphone antennae. They are a beautiful pair of locomotives. Not as polished as the LL Sets but a lot more robust.
Hope this helps.
Regards
Al
