Bring a large pot of lightly salted water to a boil.
Cook elbow macaroni in boiling water, stirring occasionally, until tender yet firm to the bite, about 8 minutes.
Drain and set aside to cool.
Combine eggs, onion, celery, bell pepper, and relish in a large bowl.
Stir together salad dressing, sugar, mustard, vinegar, celery seed, and salt in a small bowl.
Pour over eggs and vegetables.
Top with cooled macaroni; stir until well combined.
Cover and chill in the refrigerator for at least 1 hour before serving.
