'SEX' AUTHOR SCORES WITH BRITS

WHILE U.S. ambassador's daughter Mary-Catherine Lader may think English boys are the pits, "Sex and the City" author Candace Bushnell can't get enough of them. In fact, one section of her new book, "Four Blondes" (coming next month from Atlantic Monthly Press), has the narrator indulging in "three passionate days making love" with a Londoner she had first thought was gay.

As Bushnell tells the September issue of W, she had some experience on which to draw. Two years ago, the London Daily Mail hired her to write about sex in their city, with the expectation that she'd sleep with one of her subjects. She did, and was pleasantly surprised.

"This book really isn't a sequel at all," Bushnell insists. It's more "grown up" than "Sex and the City," but that didn't stop Universal Pictures from snapping up the screen rights for a solid six-figure advance.

Bushnell's characters have closely resembled her real-life conquests (Talk magazine honcho Ron Galotti as "Mr. Big" and actor/model Michael Bergin as "The Bulge"), but this time, she's treading a bit cautiously.

A trio of New York sisters has been taken out. "I changed them to twins in a later version of the book," she says. "Everyone kept saying they were the Miller sisters. I don't even know the Miller sisters - I can't tell them apart."

Bushnell is still on with her English venture-capitalist chap, Stephen Morris. They met over dinner at Rao's in Harlem when he was dating Kate Bohner. But Candace insists they didn't start dating until her friend Kate had broken up with Stephen. "I'm too much of a coward to steal somebody's boyfriend," she claims.