In the 60's the GG was a great dirty, old IND ride with R1(?)(I'm not that up on the numbers), those great steel riveted original IND's. The train had the wicker seats, the great overhead fans, compressor noise and a special IND electric smell that you only get in old cars. I used to ride from 74th down to Lorimer (?) and then catch the old BMT standards to 1st avenue. They were old and smelly with overhead fans too, but made BMT noises with a BMT smell. At some point they were jazzed up on the inside with some weird speckled green paint. The only way to get a sense of it now is, of course, at the Transit Museum. I assume you've been, if not, go.
Ron