By John S. McClenahen Economists generally look for the U.S. Labor Department to report this coming Friday, May 7, that the U.S. economy added about 168,000 jobs during April, including 5,000 jobs in manufacturing. It would be the first growth in manufacturing jobs in more than three years. New York-based UBS Investment Research is a bit more bullish. Its economists are looking for the April payroll data to show that 180,000 jobs were created -- 15,000 in government and 165,000 in the private sector, including 5,000 in manufacturing. Merrill Lynch & Co., also in New York, expects the Labor Department stats to show 175,000 nonfarm payroll jobs were created in April.