First off, many, many thanks to forumite @Mike Casatelli for the following pix. I'll take any of these (so far the only set I have is the top one (3rd-Rail Mercury), the Dreyfuss Hudson on shelf 3, and a RailSounds 2.5 board assembly from the Commodore Vanderbilt on shelf 2):
See Mike's post for more detail on his collection:
Art Deco vs Streamlined Modern / Depression Modern | Mike Casatelli
Thanks Mike!
Mike