Manufacturing companies were the sole winners of the 1998 Malcolm Baldrige National Quality Award announced Wednesday by the Commerce Dept.'s National Institute of Standards & Technology. Recipients of the prestigious award in the "manufacturing category" are Boeing Airlift & Tanker Programs, Long Beach, Calif., a unit of Boeing Co., which builds military transport aircraft; and Solar Turbines Inc., San Diego, a producer of industrial gas turbines. The winner in the "small business" category also is a manufacturer: Texas Nameplate Co. Inc., Dallas, a supplier of identification and information labels. No awards were given this year in the "service" category. Since the program began in 1988, 34 companies have received the award, named for the late Commerce Secretary Malcolm Baldrige. Starting next year, organizations in two additional categories -- education and health care--will be eligible to enter the competition.