Heh, I just finished that book a few months ago. Figger d_odds. 
IIRC, they show the clip some time in the movie “Confessions of a Dangerous Mind”, about the supposed CIA exploits of Chuck Barris, the host of the Gong Show. Probably at the beginning but maybe at the end. At least, I’m certain that I’ve seen that clip as part of a movie, and that’s the movie that it makes the most sense to have been in (among movies I’ve seen).