Following a typically hectic morning of getting the twins, Mollie and Peter, off to separate schools and attempting to coax the family dog into eating its breakfast, David Birney had a few minutes to spare for a telephone interview from his Santa Monica home - after a mix-up in time zones had been straightened out.

Birney and costar Harriet Hall will open the 1998-99 season at Park City's new George S. & Delores Dore Eccles Center for the Performing Arts with a one-night stand of Birney's own stage adaptation of Mark Twain's "The Diaries of Adam and Eve." (The performance is 7:30 p.m. Saturday, Sept. 26.)"I did this originally for American Playhouse," he said.

Before that, Birney had work-shopped a shorter, experimental version when he was teaching at Dartmouth College, where he earned his bachelor's degree in English literature.

In recent years, Birney has taken the piece on tour, including both coasts (short tours designed to fit around his children's school schedules), plus productions at the Hartford Stage and a five-week run at the Barter Theatre, the state theater of Virginia.

"And now we're opening the season for this new performing arts center in Park City," he noted.

For the past 20 years or so, Birney has maintained a second home in the Park City area. ("Mostly we're there during the summer, and we also do some skiing.") But Santa Monica, Calif., is home base. It's only a few miles from his former wife, Meredith Baxter, with whom he shares joint custody of their twins. (Birney also has an older daughter, Kate, now 23 and a graduate student in Harvard's divinity school.)

Birney has researched Twain's original humorous essays on Adam and Eve, written when Twain was in his mid-50s.

"The two pieces were written at separate times," Birney said. "Eve's diary was written after the deaths of Twain's wife and three of his children, and I've used some additional material from his letters in the script. It's the world's oldest love story, and Twain's version is extremely funny. It recalled to him his relationship with his late wife, Olivia, and it's also very moving.

"Adam encounters this strange creature with long hair. It follows him around and talks a lot. And she, of course, is always right. When their baby is born, Adam hasn't got a clue. He thinks Eve caught it somewhere."

For the "Diaries" performance, Birney and costar Hall aren't attired in fig leaves. It will have a Twain-ish look, with a Victorian gazebo, benches and a few props. Birney will be decked out in Mississippi river boat style - slacks and a gambler's vest. Hall will wear a long, white dress.

"There's a kind of prologue that opens the show about what `romance' means today," Birney said. "Ultimately, both Adam and Eve come to understand that it's better for them both to live outside the garden than inside. Essentially, the show poses what we mean when we say we love someone."

While he performs hundreds of hours of television and made-for-TV productions every year, Bir-ney's first love is performing live on stage.

"If you look at Shakespeare, Shaw and Twain - the material is very good, and I like the idea of doing performances live. Each night it's new."

Birney also does a lot of recording for audio books-on-tape.

Right now, he's looking forward to his twins' upcoming 14th birthdays, in less than two weeks. "Mollie is having `high tea,' and Peter will go paint-balling."

Birney received an honorary doctorate from Southern Utah University in 1987, when he delivered the commencement address at the Cedar City school. He commented that he'd be interested in working with the Utah Shakespearean Festival at some time. He's previously performed at the New York Shakespeare Festival, Washington, D.C.'s, Shakespeare Theatre, and the American Shakespeare Theatre in Stratford, Conn.

- WHERE AND WHEN - "Mark Twain's `The Diaries of Adam and Eve' " will be performed at 7:30 p.m. Saturday, Sept. 26.

The Eccles Center is at 1750 Kearns Blvd., adjacent to Park City High School. All seats are reserved, with tickets priced at $15, $20, $30 and $45 (the latter includes admission to a post-show reception with Birney and Hall). Box office: 328-9000 (a direct Salt Lake City line) or 1-435-655-3114.