Cook macaroni according to package instructions.In a small bowl whisk together the mayonnaise, vinegar, salt and pepper. Add a bit of pickle juice, as much as you want, milk and whisk well. Add more milk if needed, the dressing should be pourable.Cook the prosciutto in a skillet until crispy, you shouldn't need to add any oil to the skillet.In a large bowl, toss together the cooked macaroni, crispy prosciutto, olives, pickles, roasted red peppers, green onions and dressing.Serve cold.