Top executives of General Motors Corp. voiced support Oct. 21 for a stronger yen, continued investment in Southeast Asia and a "global solution" to greenhouse warming.John Smith, GM's chairman, president and CEO; Richard Wagoner, president of GM's North American Operations; and other executives were in Tokyo to introduce GM's new Cadillac Seville. They said that 100 yen to the dollar represents a good balance for the company."With the weaker yen, we have seen more exports from Japan to the U.S," Smith said. "Japanese (makers) are taking a larger share of the U.S. market." Added Wagoner: "I think the basic point is that the weaker yen has changed the competitive environment. And we'd like to see a stronger yen and a more vigorous Japanese economy to export into."GM hopes to double its annual sales in Japan by 2000 to approximately 100,000 vehicles, with continuing growth to more than 200,000 by 2005. Smith said that despite the recent economic turmoil in Southeast Asia, GM still regards the region as a key growth area for the auto industry. He said his company will continue to invest in the region."We think the impact of the devaluations will be relatively short-term," Smith said. "It is clear that some restructuring will be required, and this should improve the outlook for long-term growth." But, he said, the region's governments have to work hard to create and nurture a climate favorable to doing business to attract more auto-related investment."That means open markets," Smith said. "Open markets encourage economic growth and competitions. In many countries of the region, government policy should also place more emphasis on domestic demand rather than exports."