Place chicken in an aluminum baking pan. Pull back the chicken skin and season with garlic salt and lemon pepper. Place the skin back and season all around with the seasonings.
Pour oil into the pan and coat chicken. Let marinate for at least 30 minutes, or up to overnight (recommended).
Preheat a grill until very hot. Place pan directly on grill and cook until chicken skin is brown and crisp, about 30 minutes.