Platter removal from Zenith changer

I've acquired my first two Zenith changers (made by Zenith not VM), a 169-129 and a 169-196, both of which are identical in mechanics to the 174, 175 and 181, decor and tonearm differences notwithstanding. I cannot figure out how to remove the outer platter so I can do some cleaning and maintenance. My photofact indicates a retaining clip, but I don't see how to get to that with the 45 adaptor in the way. Any suggestions would be greatly appreciated!