Those pictures are great, too.
The 40th Anniversary DVD came yesterday for me, and I guess these are spoilers if you want to see for yourself.
It's a wonderful collection so I recommend buying it, and on the first disc they have a great special feature of Richard and Jerry performing the two-headed monster. Basically Jerry shows up late after driving from Jersey, then they film a little:
Jon: Do you guys know how you're gonna get out of this one?
Richard: No, no. We forgot that part.
Jon: It's a fade.
Richard: A fade! Well those are good.
Here's a screencap. Might make more later.
http://i37.tinypic.com/11izmzo.jpg