She chose former first lady Rosalynn Carter and journalist Cokie Roberts as speakers along with a former director of the Betty Ford Center.
Mrs. Obama, Nancy Reagan and Secretary of State Hillary Rodham Clinton with her husband, former President Bill Clinton said they would be there. And the former first lady of California, Maria Schriver, also planned to attend.
A spokesman for former President George W. Bush said he will be attending the California service and will convey condolences on behalf of his wife, Laura, who can't attend.
A second funeral will be held Thursday in Grand Rapids, Mich., where Gerald Ford is buried at his presidential museum. Former first lady Barbara Bush is expected to attend that event.
Speakers are expected to discuss politics, the White House and the Mrs. Ford's impact on substance and alcohol abuse treatment.
Roberts said Mrs. Ford asked her to give a eulogy five years ago and specified it should be about the power of friendship to mend political differences even in these hyper-partisan times.
Roberts, a commentator on National Public Radio and member of a noted political family, said Ford asked her to talk about a time in Washington when Democrats and Republicans could be friends and partisan politics did not paralyze government.
It was that way, Roberts said, when her father, Democratic Congressman Hale Boggs, was House majority leader and Republican Gerald R. Ford was House minority leader. She said they could argue about issues but get together as friends afterward. The two families became close as did the Ford and Carter families in spite of Jimmy Carter defeating Ford in the 1976 presidential election.
Carter spoke at Ford's funeral in 2007. The two families were so close that before his death, Ford asked the Carters to join his wife aboard Air Force One, which flew his body to its final resting place in Grand Rapids.
"Mrs. Ford was very clear about what she wanted me to say," Roberts said. "She wanted me to talk about Washington the way it used to be. She knew there were people back then who were wildly partisan, but not as many as today.
"They were friends and that was what made government possible," said Roberts, adding that the topic seems particularly appropriate this week when the two parties are divided over dealing with the national debt ceiling.
Roberts said she expects Mrs. Carter to talk about life in the White House and the important role of first ladies in "greasing the wheels" for their husbands' accomplishments by forging bipartisan friendships.
Former Betty Ford Center official Geoffrey Mason will also speak. Mason, a former member of the center's board of directors, is expected to extoll Mrs. Ford's vision and determination in building a substance abuse and alcohol treatment center after her own recovery.
Ford's funeral will be similar to the final tributes for her husband.
The ceremony, to be held at St. Margaret's Episcopal Church in Palm Desert, is billed as a private affair but it will be televised.
Many luminaries are due but a full guest list was not immediately available.
Following the funeral, members of the public will be invited to file past her casket and sign a guest book until midnight.
On Wednesday, her body will be flown to Grand Rapids where another church service Thursday will feature remarks by Lynne Cheney, wife of former Vice President Dick Cheney, and historian Richard Norton Smith.
Later Thursday, her body will be interred at the presidential museum along with her husband on the day that would have been Gerald Ford's 98th birthday.