Madison Avenue Potato Salad

Source: Just Recipes

3 tb Vegetable oil 
1 tb Wine vinegar 
1 1/2 ts Salt 
1/8 ts Pepper 
2 c Cooked, diced potatoes; warm 
1/2 c Quartered ripe olives 
2 Hard-cooked eggs; sliced 
1 c Thinly sliced celery 
1/2 c Diced dill pickles 
1/4 c Diced pimiento 
1 ts Grated onion 
1 tb Mustard 
1/3 c Mayonnaise

Blend together oil, vinegar, salt and pepper; pour over potatoes. Toss potatoes lightly; refrigerate. At serving time, add olives, eggs, celery, pickles, pimiento, onion, mustard and mayonnaise to potato mixture; toss.