3. Meanwhile, preheat grill. Squeeze juice from the remaining lemon into a small bowl, whisk in the remaining 1/4 cup oil, and season to taste with salt and lots of pepper, then set aside. Remove chickens from marinade, discarding marinade. Grill birds over medium-hot coals, basting occasionally with the reserved lemon and oil, until skin is well browned on both sides and thigh juices run clear when pricked with a fork, about 50 minutes. Set chickens aside to rest for 10 minutes, then cut into quarters.