Preheat the oven to 325 degrees F. Heat the oil in a large skillet. Season the meats with salt and pepper; brown on all sides. Transfer to a large, deep casserole. Cut 1 lb. of the potatoes into thin slices; set on top of the meat. Pour in the stock. Cover and cook in the oven 90 minutes. Cut the rest of the potatoes into 1-inch cubes. After 90 minutes, give the scouse a stir to break up the sliced potatoes (this will help thicken it). Mix in the uncooked potatoes, onions, carrots and Worcestershire sauce; cover and cook 60-90 minutes more, or until the meat is very tender. Adjust the seasoning and serve.