George did his lettering with a brush from everything I've read and from the people I've talked to who knew him. When I got my first Stock GG1 in 1995, I had recently moved to Phoenix from one of the suburbs and found it at a local swamp meet for $10. It was missing a lead truck, one of the pantographs and the motors. Lou English senior was the one who ultimately helped me identify it around 1995, but even he told me "I never knew George made a GG-1".
Not to steal this thread, but an article I put together for my TCA Division newsletter years ago on the GG1s. Posted here before, but not in a while. In the years since I wrote this many have corresponded with me to fill in the back story on George and his wonderful contributions to this hobby.