A. McWilliams was Alden McWilliams, incredibly prolific, incredibly talented comic artist who drew a scadillion comics pages and drew, ghosted, or assisted upon at least as many newspaper strips. Being a huge fan I could gush about him forever...suffice it to say he drew in the Raymond/magazine style used by Williamson and the two are often confused. McWilliams had done work for other Transportation Workers projects, so I'm guessing when the book was reprinted Williamson wasn't available and they asked McW to do a new cover.