Japanese auto-maker Mitsubishi is set to increase the number of U.S. dealers by 50 to a total of 600 within the next three years, company officials said on Wednesday. The expansion will help Mitsubishi achieve its aim of selling 400,000 vehicles in the U.S. by 2005. The company sold 314,417 units in 2000 - a rise of 20.3 per cent from 1999 - a record level for the second consecutive year. Sales of all models were strong - especially those of the Montero Sports SUV and the U.S.-built Galant sedan.