Pull off any strands of flesh from pumpkin seeds; rinse seeds well. Let seeds dry on paper towels for several hrs. In a medium mixing bowl, toss seeds with oil, salt, garlic powder and most of the zest. On a baking sheet lined with parchment paper, spread seeds out in a single layer; roast in a preheated 375° oven, stirring once or twice, until seeds are dry, sizzling and dark golden-brown in places (about 15 min.). Cool completely; season with reserved lime zest and salt to taste.