It's the equivalent of putting together in eight weeks a Broadway musical variety show with a cast of 170 stars, 200 musicians and a potential audience of upward of 70 million.

And the first rehearsal isn't scheduled until two days before the night the show opens.

In Beverly Hills, Calif., Yesterday, James Lipton, executive producer of the CBS-televised Inaugural eve concert at the Kennedy Center, seemed remarkably calm in the face of these facts.

It was President-elect Jimmy Carter himself who supplied the theme to pull together the acts and stars, which Lipton said he chose himself without any "political considerations.

"It's that early morning in Plains, Ga., at dawn on the morning after the election," says Lipton, with dramatic flair for setting the scene.

"The sun rises, as Jimmy Carter says, on a 'beautiful new day' and a 'beautiful new spirit in this country.' That's our theme."

As the executive producer, Lipton says he made his decisions as a showman on how to put together the New Spirit Inaugural Concert. The politics of the performers didn't enter into his considerations, he emphasized.

"Gov. Carter did not specify any artists" the producer added. "There were no prohibitions, no insistences."

The Inaugural Committee stressed only two things, Lipton said: that there be no "political considerations" governing the show and that it be an evening of "lighthearted entertainment" in tribute to the "country, the people, and variety of our arts."

Lipton said he sat down in his study, thought about the show and then began calling performers, who will appear for a minimum fee in the hall donated by the Kennedy Center.

Lipton promises "irreverent" comedy, classical and popular music, poetry, movie stars and modern dance for the 2 1/2 hour show.

Comedians Chevy Chase, Red Fox and Freddie Prinze are writing their own material. And Mike Nichols and Elaine may, who made up a brilliant team of satirical comedians a decade ago before they went their separate directing ways, will be reunited in a skit.

Chevy Chase, who stumbled to fame with his pratfalls in skits on President Ford, has a "positively brilliant satire," Lipton said. But he wouldn't say whether Chase will be imitating Carter because "that would give it away." The President-elect is expected to be in the audience.

Lipton says he chose the performers in hope of giving pace and change to a program designed to capture the variety of the arts in America.

There will be world-premiere songs by Leonard Bernstein (part of a 14-part song cycle and dedicated to the future First Lady Rosalynn Carter) and Paul Simon. Opera star Beverly Sills, country music star Johnny Cash and singer-composer Stevie Wonder will sing. Poet James Dickey will read a new work. The Alvin Alley American Dance Theater will perform. Among the movie stars appearing will be John Wayne, Bette Davis, Paul Newman, Sidney Poitier and Joanne Woodward.

The show will begin at 7 p.m. for the live audience in the Kennedy Center. It will go on line to New York City to be taped for commercial inserts. The CBS television program, for which the network is giving $250,000 to the Inaugural Committee, will begin at 9 p.m.

Lipton's experience includes having written two Broadway musicals, "Sherry," a musical based on "The Man Who Came to Dinner," and "No Where to Go Except Up."

"What normally takes two years is being done in eight weeks," he said as he prepared to fly here for the first rehearsal of the Inaugural concert on Monday.