Macaroni Salad

3 c shell macaroni
2 c cubed cheese
1 c chopped celery
½ c chopped green pepper
¼ c chopped onion
¾ tsp salt
1c sour cream
1c mayonnaise
¼ c milk
½ c sweet pickle relish
2 tbs vinegar
2 tsp prepared mustard

Chill several hours