Rich, I have quite a few recipes for cooking liver with different ingredients, but this is the most different one I have. Never thought to marinate liver. 
(and it's for the grill)
Marinated Liver Steak
1 1/2 cups dry red wine
3/4 cup chicken stock
2 TB. olive oil
1 TB. vinegar
1 TB. lemon juice
1/2 medium-sized onion, chopped
1/2 cup minced parsley
1 1/2 bay leaves, crushed
1 tsp. whole thyme
1/2 tsp. whole basil
1/4 tsp. whole oregano
1/4 tsp. whole tarragon
1/4 tsp. whole rosemary
2 lb. piece beef liver, 2 to 2 1/2" thick
1. Combine in a pan all ingredients except the liver. Bring to a boil, reduce heat and simmer 2 minutes. Cook 5 to 10 minutes; then pour over liver. Cover and refrigerate for 24 hours to 3 days.
2. To cook liver, drain and place over medium-hot coals, 10 to 12 minutes per side for rare; turn once and baste often with marinade. Makes about 6 servings
Source: Sunset "Barbecue Cookbook" 1972
(and it's for the grill)Marinated Liver Steak
1 1/2 cups dry red wine
3/4 cup chicken stock
2 TB. olive oil
1 TB. vinegar
1 TB. lemon juice
1/2 medium-sized onion, chopped
1/2 cup minced parsley
1 1/2 bay leaves, crushed
1 tsp. whole thyme
1/2 tsp. whole basil
1/4 tsp. whole oregano
1/4 tsp. whole tarragon
1/4 tsp. whole rosemary
2 lb. piece beef liver, 2 to 2 1/2" thick
1. Combine in a pan all ingredients except the liver. Bring to a boil, reduce heat and simmer 2 minutes. Cook 5 to 10 minutes; then pour over liver. Cover and refrigerate for 24 hours to 3 days.
2. To cook liver, drain and place over medium-hot coals, 10 to 12 minutes per side for rare; turn once and baste often with marinade. Makes about 6 servings
Source: Sunset "Barbecue Cookbook" 1972