Compiled By Jill Jusko Even before it has completed construction of its new manufacturing plant in Canton, Miss., Nissan North America has announced plans to expand the plant by 1 million square feet. The company says it will invest $500 million for the 1 million-square-foot addition to the 2.5 million-square-foot plant currently being built. As a result the plant's annual capacity will rise from 250,000 vehicles to 400,000 vehicles and add 1,300 more jobs to the plant's workforce. Production at the Canton plant is slated to begin in the spring of 2003. Nissan North America, which is based Gardenia, Calif., says the expansion will accommodate additional production of the Nissan Altima, which also will continue to be built at Nissan's plant in Smyrna, Tenn. Also slated for production in Canton are a full-size pick-up truck, full-size sports utility vehicle and a minivan. Construction of the Canton plant began in April 2001.