In the limited time leading up to shooting, Williams and his credited assistant (and future wife) Marsha Garces had to start researching. Williams went to Thailand (Bangkok played the part of Saigon in the movie) and, thanks to a historical consultant, began reading up on soldiers’ slang in Vietnam in 1965 and immersed himself in the pop culture of the time — avoiding the embarrassment of dropping an anachronistic TV reference. Williams wrote down many notes as to what topics would be verboten: Kinks, Beatles, Top 40s, psychedelic, etc. Williams also learned some pretty crass shorthand. “Ho Chi Minh’s Revenge” was, for instance, an American Army term for diarrhea. Other nicknames the military boys had developed were even less couth.
Then, at night, he and Garces would return to their hotel room and workshop Cronauer’s ranting monologues. This type of workshopping and testing material is more traditionally done on long tours and extended gigs in comedy clubs; most high-profile comedians hone their jokes and test material over the course of many months or even years before the recorded special makes their way to an audience. As there were no comedy clubs in Bangkok — and because time was at a premium — Williams simply tested out his work on Garces. Garces essentially co-authored Williams’ rants in the movie.
With a good deal of material to draw from, Williams then had to perform it. The in-booth Cronaur scenes only make up about 12 minutes of screentime in the movie, but they are the defining feature of it.