Sweet Horseradish Pickles

2 quarts dills pickles,  drained,  sliced thick and rinsed
2 cups sugar
1 tablespoon dry mustard
2 teaspoons celery seed
2 teaspoons whole mustard seed
2 garlic cloves, sliced
1 1/2 cups water
3/4 cup vinegar
1 small onion, thinly sliced.
4 tablespoons horseradish

Wash slice dill pickles, wash and place into quart jars. Mix sugar and dry mustard in a large bowl or measuring glass. Add remaining ingredients. Pour over pickles. Let stand at least four days in the refrigerator. Keeps well.