Whisk grapefruit zest, grapefruit juice, and honey in a bowl.
Season the pork rib chops with ¼ teaspoon each salt and pepper. Grill for 7 to 9 minutes per side. Continue grilling, basting with the grapefruit mixture, for 2 to 3 minutes.
Let rest for 5 minutes. Drizzle any juices on top and serve with grapefruit wedges and a green salad.