Actually, GE moved their TV production to Portsmouth in the mid 70's. GE closed up shop in Portsmouth in the late 80's, after their "PC" chassis sets.
GE used a parts numbering system that identified where the end item was manufactured. ES series parts were for Syracuse sets, EP for Portsmouth sets, and EW was offshore (Taiwan and Singapore, mostly). EA was early GE audio stuff. Confusingly enough, similar parts were not the same. An ES15X1 transistor wasn't (at first) the same as an EP15X1. Made things tough for dealers and distributors. ET was also used for early stuff - not sure of the location of manufacture.
A couple of anecdotes about the GE plant. When I was working for Cain Electronics in Norfolk, VA in the early 80's, the GE plant engineering department would purchase RCA TV parts from us to dissect. Mostly RF stuff - varactor tuners, baluns and the like. Guess they wanted to examine the competition.
When the plant closed down, they auctioned off some parts and tooling. My dad and another gentleman here in Norfolk, both TV repairmen, got the engineering department parts stock. Fun stuff to sort through - 80,000 film resistors, CRTs that hadn't been UL tested/listed yet, loads of assemblies, and mock-ups of future TV models. They had a metal case PC chassis set loaded with options - MTS stereo, video and audio input/output jacks, and even take-off points to a patch panel on the side. We never did get that one to work - too many modifications to deal with.
