Brakes supposed to ride on "hub"??

You should have some clearance between the hub and the bottom of the caliper On my Duster, I guesstimate I have about 3/8" - 1/4" of clearance from the top of the hub to the bottom edge of the brake pad when installed. As for the clearance from the hub to the bottom of the caliper, I would think that you would have at least 3/4" - 1" of clearance to work with.