Gerald R. Ford and Ronald Reagan Tuesday attempted to show that the Republican party can multiply without dividing.

Returning, ironically, to the state where the former president lost the bitter 1976 presidential primary to the former California governor, Ford and Reagan made their first joint political appearance since the Republican National Convention more than two years ago.

They warmly shook hands. They saluted each other with kind words. They laughed at each other's jokes. And they did all of this as their own political futures, perhaps conflicting again, are speculated upon and even as two other potential Republican presidential hopefuls sat with them before some 1,300 cheering Republicans.

It could have been a group photo session of the Republicans' presidential Class of '80: Ford, Reagan, former Texas governor John Connally, and former central intelligence director George Bush.

Or depending on the turn of events, maybe it was only a reunion of the graduates of '76.

So remarkable was the outward display of unity and Texan ambition that former U.S. ambassador to Great Britain and now Texas rancher Anne Armstrong was moved to declare: "I am the only [speaker] with absolutely no aspirations to be the next male president of the United States."

Instead she is frequently talked about as a possible vice presidential nominee.

Ostensibly, Ford and Reagan were here to pump the candidacy of Texas Republican gubernatorial candidate Bill Clements, and the joint appearance at $1,000 a plate raised $1.3 million for Clements, a former assistant secretary of defense for presidents Ford and Nixon.

"Neither [Ford nor Reagan] wanted to be upstaged in Texas," said one Republican, however, of the possible political positions of the two men in the nation's third most populous state. "They don't want to be caught not here if Clements wins."

Another Republican, Jim Baker, Ford's 1976 national campaign chairman and current GOP attorney general candidate here, observed, however, that the two rivals did not have to appear together and added that the sense of unity - despite pockets of cheers for favorites - is real.

At least for now.

Their day began in Houston with a scrambled egg and link sausage breakfast with key Clements supporters. Then while Reagan spoke in San Antonio, Ford and Clements drew cheers from some 7,000 students at the University of Texas in Austion. There, both were made honorary cowboys and sang "The Eyes of Texas Are Upon You" while displaying a hooker-horns fist - an index and little fingor salute.

Then Regan joined the Ford-Clements airplane and together the three flew here for an airport rally and fund-raising dinner of medallions of beef tenderloin and Bolla wines from 1975 and 1977, as if the year 1976 had been cast aside even on the menu.

Reagan, whose renewed campaign for the presidency is all but declared, directed his words at the Carter administration and national issues and traditional values. Basically he expressed his well-known views and made only scattered references to Clements.

In one interview he apparently said cheerily - and accidentally - that thing look "great for hill" - Clements' opponent, state attorney general John Hill.

Reagan's dinner speech repeated Jimmy Carter's inaugural address tribute to Ford, "For all he has done to heal our land."

Ford, perhaps reflecting the muddled nature of his own plans, concentrated most on praising Clements in speeches that also took swipes at Carter. The former president says he is enjoying his retirement and urges that Carter also retire early, like a 1961.

In an airport tarmac interview, Ford said he was in Texas "solely and exclusively" to help Clements and not to maintain a political base here. Of his plans, he said: "We've got lots of time, many options, and I'm just not going to get involved in giving you any answers on what my plans are."

He said his decision on another run for the White House is not related to the campaign successes of Bush, who has obtained support from some key party operatives who backed Ford in 1976.

Whatever the spirit of harmony that prevailed here Tuesday, the opportunities for conflict remain strong. The 1976 presidential primary was the only one ever held in Texas under a one-time law passed by the Democratic state legislature to give Texas Sen. Lloyd M. Bentsen a shot at the Democratic nomination.

But last weekend the state Republican convention voted to hold a 1980 presidential primary, a move that could bring a court challenge to the state's election laws as well as showdown campaigns like that of 1976.

Republicans see the primary as a way to win over conservative Democratic voters, a move that could both multiply and divide the Republican party here.