Have you tried swapping the pads from front to rear? You do understand that if it's not rubbing all the time, there has to be some runout to the rotor? How much rubbing is going on? If it's only a little, and you're satisfied that you've done everything right, there's only one thing left to do. Make sure it's all tightened, and go for a ride. Make it at least a few miles, with 20 or so decent hard stops. Then get back to us.