Upgraded with some good images of her butt:
Gene Wilder plays Quackser, an independent, none-too-bright guy from a working class Dublin family in the horse-and-buggy era. Quackser doesn’t want to spend his life working in a factory as his dad did, so he creates a profession for himself. He follows the horse-drawn delivery wagons around Dublin, shovels up the horseshit from the streets, and resells it from a pushcart, as fertilizer. (“Get your fresh dung”!) He loves this job, the city loves him for it, and he is generally loved by everyone he meets along the way.
Unfortunately the modern world is encroaching on the world Quackser has built for himself. Motorized vehicles are arriving, the horses are going to be shipped off to unpleasant fates, and Quackser himself seems destined for a Dickensian future, since he’s illiterate and has no skills.
This is the kind of film that sounds terrible on paper, but works, thanks to a consistent tone and appealing performances. It is odd, but an inexplicably compelling movie.
Then unknown Margot Kidder, just 21 at the time, nearly a decade before she would reach stardom as Lois Lane, never looked more beautiful than she did here, playing the love interest of sorts. The adventurous American college student takes on Quackser as a lover, but doesn’t really respect him. She gradually seduces him, and poor Quackser thinks it’s love, but for her it’s a frolic that she has already regretted by the time they actually sleep together.
You can watch the entire film for free on YouTube. The sex scene begins about 64 minutes in.
The film is now available in Blu-Ray. Video.

I read that as Gene Hackman at first and I thought, Wow, what a horrible miscast!
Her B&W beach shoot that was in Playboy in the 70s were her hottest nudes