Preheat oven to 300°.
Combine first 5 ingredients in a large heavy-duty zip-top plastic bag. Combine margarine and remaining 4 ingredients; pour over cereal mixture. Seal bag; shake well to coat.
Place cereal mixture on a 15- x 10-inch jelly-roll pan. Bake at 300° for 18 to 20 minutes or until lightly browned, stirring occasionally. Remove from oven; let cool completely.
Store snack mix in an airtight container.