By coincidence, I receieved a few days ago (from Steve Palmano) a copy of the write-up on these locomotives in the British magazine "The Railway Gazette" for 18 April 1952. The article describes the locomotives as "designed and built by the General Electric Company of the U.S.A." and mentions a technical write-up in a paper presented to the AIEE by three authors, all from "the Locomotive and Car Equipment Department, the General Electric Company, Erie, Pa." There is no mention of Alco.
There was no reason for Alco to be involved. GE had occasionally used Alco-built carbodies for its early electric locomotives, but by 1952 had been building complete locomotives at Erie for at least two decades: for instance, some of the P5a and GG-1 locomotives of the Pennsylvania Railroad. The PRR E2b was a straight AC locomotive, and its trucks-- though looking a bit like the "Type B" trucks used on contemporary Alcos-- had a longer (11 foot) wheelbase and 48" wheels. Thus they had little in common with contemporary Alco-GE diesel-electric locomotives, which had DC traction motors geared to 40" wheels.
The only feature suggesting Alco affiliation is the carbody shape (in particular the cab and nose), which resemble the Alco FA diesel. The FA's carbody design, however, seems to have been (like the PA's) due to GE's industrial designer Ray Patten: so, a GE contribution to the Alco-GE product. Similar, though not identical, cab designs were used on GE's EP-5 electric locomotives for the New Haven (as Super Seis said) and, with a different headlight casing, GE's gas turbine electric locomotives for the UP.
The E2b is a fascinating locomotive: built in the diesel era, it had a carbody configuration similar to that of contemporary diesels, but in its bsic AC technology it was more of a development of the sort of AC locomotive that PRR had traditionally used. I regret that all were scrapped before I became enough of a railfan to try to seek them out.