Whisk together the oil, lemon juice, 1 tablespoon of the zest, 6 cloves of the garlic, and 3 tablespoons of the rosemary in a large baking dish. Add the chickens and turn to coat. Cover and marinate in the refrigerator for at least 1 hour and up to 8 hours.
Combine the parsley with the remaining 2 teaspoons lemon zest, 4 cloves of garlic, 1 tablespoon rosemary, 1/4 teaspoon of the salt, and 1/4 teaspoon of the pepper in a small bowl and set aside.
Heat your grill to medium. Wrap 4 bricks in aluminum foil and set aside.Remove the chickens from the marinade, shaking off the excess, and season both sides with the remaining 1 teaspoon salt and 1 teaspoon pepper. Place the chickens breast side down on the grill and place 2 bricks on top of each chicken. Grill the chickens for 8 to 10 minutes, turn the chickens over, and replace the bricks. Close the cover and continue cooking for 8 to 10 minutes until cooked through (160 to 170 degrees F).
Transfer the chickens to a cutting board and let rest for 10 minutes. Cut into quarters and sprinkle with the fresh lemon mixture. Serve with grilled lemon wedges.
*To Butterfly Chicken:.
Place the chicken breast side down on a cutting board and cut along each side of the backbone using kitchen shears or a sharp knife. Remove the backbone and discard. Turn the chicken breast side up and pull out each side where the backbone was removed. Using the heel of your hand to press down on the breast, break the breastbone to flatten the chicken.