Blend garlic, seasoned salt, oil, lemon juice, dressing, onions, pepper, and thyme. Marinate the birds overnight in the refrigerator. Cut the birds lengthwise. Cook on outside grill bone side down 10 minutes, flesh side down 5 minutes, alternating 10 minutes and 5 minutes in this manner for 1 hour and basting with marinade frequently (at least every 5 minutes) while cooking.
Oven method: Preheat oven to 400° F. Place skin side up in a shallow pan, baste with marinade, cover with foil and roast for 30 minutes. Remove foil and brush with marinade again. Roast again uncovered for 20-30 minutes. (Test for doneness: drumsticks should be soft and juices should not be tinged with pink when you pierce the thickest part of the thigh with a fork. Brush with marinade twice more during this second roasting period.
Servings: 6 to 8