Bring a large pot of salted water to a rolling boil. Add dry macaroni and cook according to package instructions, 8-10 minutes. Drain and rinse under cold water.

In a mixing bowl, combine diced corned beef, cubed Swiss cheese, drained sauerkraut, and diced dill pickles. Mix well.

In another bowl, whisk together Thousand Island dressing, mayonnaise, Dijon mustard, and sauerkraut brine until smooth.

Gently fold cooled macaroni into the corned beef mixture. Pour dressing over everything and mix until evenly coated.

Cover and chill in the refrigerator for at least one hour to enhance flavors.

After chilling, stir gently and adjust seasoning with salt and pepper if needed. Serve cold.