Fill a large pot ⅔ full with water. Add the salt and bring to a boil. Add the macaroni and cook until al dente. Drain.
In a medium pot, combine the heavy cream, evaporated milk, American cheese, Parmesan cheese, and Romano cheese. Cook over medium heat until the cheese has melted, stirring frequently to prevent scorching.
Turn on the broiler. Place the cooked pasta in a 9x13-inch casserole dish, pour the cheese sauce on top, and sprinkle with Colby Jack cheese. Broil until the cheese just begins to brown.
