When doing my discs and pads last weekend, besides my corrosion under shim issue, I discovered that the lower piston on the inside of the passenger caliper has seized. As a result I can feel a, thankfully only slight but annoying none the less, pull to the left. I've seen the seal kits on ebay but can't find a guide to tearing the caliper down. Is it a difficult job or does anyone have a guide or done their own rebuild? Many thanks as always.