GREENFIELD — A high-tech metalworking tool manufacturer in Greenfield has announced a nearly $5 million upgrade that is expected to bring 70 new jobs to the region.Kennametal Inc. plans to invest $3.4 million immediately on upgrades to the plant, equipment and machinery, as well as another $1.25 million over the next four years.Greenfield Mayor William Martin tells The Recorder the 70 jobs the company plans to add will provide an average income of $75,000 per year.