1993 Ford F150 rear drum brakes dragging

i had a front caliper come apart and drained the brake system of fluid. i have replaced both front brake rotars, calipers and pads. i have also replaced the rear drums, shoes, springs, and wheel cylinders. also have replaced the master cylinder. Now the problem is that the rear passenger side brake is dragging and getting hot. i have ruined one set of shoes because of this. i have bled the brakes but has not helped. when the brakes are appiled pretty hard the abs and brake lights come on. please help
thanks bill