For more than a decade, county and local officials have referred to North Texas Regional Airport — Perrin Field as the region’s unshined jewel. While the former military base had ample opportunity to shine, it just needed proper investment and the right leadership to polish it.Now, new leadership is stepping in with plans of converting the unpolished gem of Grayson County into a gold mine for the community.New NTRA Manager Kyle Holtz recently sp…