Go take a flying fuck at a rolling donut (idea)

This phrase is actually from Kurt Vonnegut's book Slapstick. The protagonist uses it, and then when he's President of the U.S. he tries to get into a private club. The club is only for people with a certain middle name (as President, he'd had everyone in the U.S. assigned a government-issued middle name) and he didn't have it. The doorman asks him if he's got that name, and he says of course not. The doorman says "Then, sir, I must respectfully ask you: why don't you go take a flying fuck at a rolling doughnut? Why don't you take a flying fuck at the moooooooon?"

Of course, there are other possibilities:

• I'm imagining all this (it's been 15 years or more since I read the book)
• It's in both this book and Slaughterhouse 5 (more likely)
• I'm on crack (you'll never know!)