(Courtesy http://www.scgaynor.com/)
Brown (left) and Gelman, are clearly on the set of the Soupy Sales show as Topps was doing their thing to promote the 1965 upcoming card set. This was not the actual shot used, or at least I don't think it was as one clearly taken within seconds of this one has been uploaded over at http://www.nsu-magazine.com/ for some time now and seems to be the money shot, although I only know this since I started researching the above picture:
Kind of a dour look from the Topps boys, no? That Mars Attacks logo pegs the second scan to Topps proper methinks. I also have to think this shot was the one used officially. I tend to be in the 1965 camp for the Soupy set, although most sources cite 1967. Either is possible but there seems to be more evidence for the earlier date, at least to my mind, as Soupy-mania was in full swing in 1965.
Len Brown was a protege of Woody's and perhaps his most successful one. Brown succeeded Gelman as Creative Director of Topps, having been hired by Woody as a 17 year old. Brown worked on such things as the 1960 Baseball set, Mars Attacks, Civil War News and obviously Soupy Sales before ascending to Woody's old position upon the latter's retirement (which I think was in 1972).