GM will become the first major automaker to produce a fleet of natural gas-powered vehicles, the Houston Chronicle reported. A consortium of pipeline companies and producers will help pay for and purchase the 1,000 light trucks.

Chrysler stock rose again as speculation continued about talks over a possible major link between the struggling automaker and Italy's Fiat SpA. Chrysler finished up $1.12 1/2 at $16.62 1/2.

The U.S. economy, powered by exports and capital goods, will register real growth of 2.4 percent this year, according to a new Conference Board forecast. Growth is expected to slow, however, to 2.2 percent in 1991, reflecting a weaker industrial economy, the report said.

Kenneth Leibler, president of the American Stock Exchange, will leave that post to become president of the Liberty Financial Companies, a wholly owned subsidiary of Liberty Mutual Insurance.

Ames Department Stores, struggling under the weight of bankruptcy proceedings, reported first-quarter losses of more than $430 million. In the same quarter of last year, Ames lost $16.5 million.

Circus Circus opened the 4,032-room Excalibur hotel -- said to be the world's largest -- in Las Vegas. The hotel was built for $290 million, and rooms start at $45 a night.

Japan's economy grew 5 percent in the past fiscal year, boosted by 2.5 percent fourth-quarter activity, the government said. It was the third straight year in which Japan's gross national product expanded 5 percent or more.