Mix Marinade Mix, oil, bourbon and orange juice in small bowl. Reserve 1/4 cup marinade for brushing. Place pork in large resealable plastic bag or glass dish. Add remaining marinade; turn to coat well. Refrigerate 2 hours or longer for extra flavor.
Meanwhile, preheat oven to 400°F Prepare corn muffin mixes as directed on package. Spread evenly in greased 13x9-inch baking pan. Bake 15 to 20 minutes or until golden brown. Cool completely on wire rack. Cut cornbread into 1 1/2-inch strips, then cut each strip in half. Grill over medium heat 1 to 2 minutes on each side or until grill marks appear, turning once with a wide spatula. (Do not use tongs as cornbread is fragile and tends to crumble.) Set aside.
For the Grilled Peaches, mix Marinade Mix, brown sugar, melted butter and bourbon in large bowl until well blended. Add peach slices; toss to coat well. Let stand 1 hour. Fold the edges of a sheet of heavy duty foil to form a shallow baking pan. Place on grill over low heat. Place peaches on foil. Cover with second sheet of foil. Grill 6 to 8 minutes or until peaches are browned and caramelized around edges, turning occasionally and brushing with marindae. Set aside.
Remove pork from marinade. Discard any remaining marinade. Grill pork over medium heat 25 minutes or until desired doneness, turning occasionally and brushing with reserved marinade halfway through cooking. Discard any remaining marinade. Let pork stand 5 minutes. Cut into 1/4-inch slices.
To serve, warm peach preserves. Spread evenly on cornbread strips. Cut each cornbread strip into 1 1/2-inch squares. Place 1 slice pork tenderloin and 1 grilled peach slice on each cornbread square.