PREHEAT oven to 325°F. Mix hot water and margarine in large bowl until margarine is melted. Add stuffing mix; stir just until moistened. Set aside. (Do not stuff chicken until ready to bake.)
STUFF chicken lightly with prepared stuffing; close openings with skewers and string. Place, breast-side up, on rack in baking pan; sprinkle with thyme.
BAKE 1 hour 40 min. or until chicken is cooked through (180°F) and stuffing is heated through (165ºF), basting occasionally with the pan juices.