I see it's been almost a month without a response, so I'll offer what I have. My experience with Erie gas-electrics was limited to the 1940's on the suburban lines out of Jersey City, which were all of the same class (I think 5010 and up); the one I saw most was 5012 on the NYS&W, and while painted and lettered for the Susquehanna it was the same class as those on the Erie itself. Those were the standard Erie dark green like the Stillwells (in fact the passenger portion had a Stillwell-type roof), with horizontal yellow stripes on the motor end which I think bent around from the front to the side and ended with the ends cur off diagonally along a line sloping forward and downward from the longest (top) stripe to the shortest (bottom) stripe. If you can find some black-and-white photos of the period, the stripes were yellow and the body green. In service the cars were rarely washed, and it was hard to determine what the original color was. I don't know whether this is any help, since I know the Erie had other types in western New York, and prior to the 1940's; the only books I have seen have only black-and-white photos, understandably, and the text didn't mention the color, so possibly that means there was nothing out of the ordinary about it.