Peel shrimp, reserving the shells. Cut shrimp in half lengthwise; cover and chill. Combine the reserved shrimp shells, Chicken Stock, and sliced garlic in a large saucepan. Bring mixture to a simmer, and cook for 15 minutes. Drain in a colander over a bowl, reserving broth mixture. Discard the shrimp shells. Return broth mixture to saucepan.
Add the tortillas to broth mixture; let stand 10 seconds or until soft. Remove tortillas from broth. Place tortillas, salt, and next 4 ingredients (salt through chile) in a blender; process until well-blended. Heat oil in a large nonstick skillet over medium-high heat; add tortilla mixture. Cook 5 minutes, stirring frequently. Stir tortilla mixture into broth mixture. Bring to a boil; add shrimp and fish. Reduce heat; simmer 3 minutes or until seafood is done. Serve with lime wedges.