You were supposed to talk at the stockholders' meeting only if you had something to say, presumably something important, about company business.

So the Chrysler Corp. stockholder from Missouri thought he was within his rights when he went to the microphone and said: "Mr. Chairman, I just want to say that I see you on TV a lot, and I like your commercials . . . My wife likes them, too."

Chrysler Chairman Lee A. Iacocca responded with a thin smile and a deadpan comment: "Well, if you like them so much, go out and buy a car."

Iacocca said two things about himself with that response. One, he really doesn't like doing the television commercials that have helped to put his company, once riding near bankruptcy, back on the road to solvency. Two, his overriding interest--and the only reason he has ever considered doing the TV spots--is in making Chrysler and the overall U.S. auto industry competitive again.

"I don't see myself doing many more commercials," Iacocca told a reporter after addressing his company's 57th annual stockholders meeting in St. Louis 10 days ago. "These things are time consuming. They take you away from other business."

Iacocca has done 19 of the commercials since 1980. The ads, produced by the New York-based public relations firm of Kenyon and Eckhardt Inc., have helped boost sales of Chrysler cars and trucks from 910,352 in 1980 to 1,011,864 in 1981. They have also propelled Iacocca, who speaks in machine-gun bursts, to the forefront of the battle for the domestic auto industry's survival.

Iacocca is "the auto industry's Patton in pinstripes," veteran auto industry observer J. Patrick Wright recently wrote in "Midwest Business," a quarterly supplement to the magazine Monthly Detroit. He "is the most prominent and talented top executive in the auto industry . . . though his company collects only 10 percent of the domestic industry's business."

Executives at General Motors Corp., the nation's largest automaker, and at Ford Motor Co., the second largest, might quibble with the "most talented" label. But, thanks largely to the commercials, the 57-year-old Chrysler chairman safely could claim the "most prominent" award.

Iacocca began the television ads with a 30 percent "name recognition factor," says Glenn Campbell ("I'm not the singer"), spokesman for Kenyan and Eckhardt. Today, about 80 percent of the American public recognizes Iacocca, as well as his company's pentastar symbol. To many people, Iacocca and Chrysler have become one, according to Campbell and other advertising executives.

That is why Chrysler officials get a little nervous when Iacocca starts grumbling about doing commercials.

"Well, uhm, he says these things from time to time," said Chrysler spokesman Baron Bates, commenting on his boss' remark about bowing out of the "time consuming" ads. "That's sort of his stock answer." However, Bates conceded that there are no plans to use Iacocca in 1983 advertisements.

"But those plans are subject to change, because he has been very effective for us," Bates added. "We probably would use him if we had to do something really big."

Iacocca became Chrysler's chairman 3 1/2 years ago after being unceremoniously bounced from his job as president of Ford, where he had worked 32 years. Since his arrival at Chrysler, he has always been called upon to do something big. Not the least of those chores was his act of corporate begging in 1979 that brought Chrysler $1.2 billion in federal loan guarantees, keeping it in business.

Later that same year, Iacocca was called upon to do tag lines--brief announcements at the end of commercials. The tags worked so well the folks in the corporate advertising department at Chrysler got a better idea: Why not make Iacocca the star, of sorts, of full-blown television ads?

"We had to do a selling job on him to get him to do it," said Joseph Hickey, Chrysler's manager of corporate advertising. "Iacocca doesn't want to come off as a television personality or a performer. So we had a lot of resistance."

Iacocca continued resisting, even after getting a couple of the commercials under his belt, Hickey recalled. Partly as a result, "We figured that we should only use him when we had to. He's become our 16-inch gun. We don't want to waste him."

That meant not using Iacocca to "do pitches"--to plug sales rebate programs, for example. Instead, it meant using him to push so-called corporate breakthroughs, such as Chrysler's "new" five years or 50,000 miles warranty program. (A similar "5/50" program was introduced in 1962 by then-chairman Lynn Townsend.)

Using Iacocca for "something big" in commercials also meant talking up Chrysler's revived commitment to quality. But the latest ad in this category--which concludes with his saying, "If you can find a better car, buy it"--has proved a tad controversial.

Some people thought Iacocca was being arrogant, Hickey said. "I got a letter from a businessman saying that if he told his customers that, he wouldn't have any more customers."

But Hickey said the "overwhelming response" to Iaccoca's tough-sell ad has been positive.

"People say they believe it demonstrates Iacocca's confidence in his products," Hickey said. "That's the way Iacocca feels. Those are his words. Nobody made them up for him."

There is an air of aggressive humility nowadays in Chrysler headquarters in Highland Park, near Detroit. Bates, Hickey and others say that the company has learned from its past failings and has become a bastion of born-again commerce. They point to Chrysler's $900 million in cash reserves, its increasing sales, and to Iacocca's relatively modest office on the fifth floor of the company's even more modest looking K.T. Keller building.

As always in these ruminations, there is the hidden fear that Iacocca may do more than bow out of ads, that he might bow out altogether.

"I think it's as much a mystery to him as anyone else" as to when Iacocca might resign from Chrysler, one company official said. "Nobody dares ask him."

In another breath, the official reassures himself: "I don't see anyway" that Iacocca will quit soon. "He's so committed. . . . If things had continued to go downhill, I don't see how he could have stood up. But when you have nearly $1 billion in cash, you have a different perspective."