I drove my Defender about 15-20 miles with lots of braking with a rubbing sound in the front end. While replacing pads today, I noticed the front right pads were really hard to remove. Once out, the inside pad looked brand new as far as thickness but the outside pad was worn completely out. Now I can only press out the piston maybe 1/4 inch. Are there any pointers on pressing it all the out so I can get the new pads back in?