The whole brake assembly saw its day long ago, and has the rust to prove it. The caliper is being removed here; hubs and rotors come next. Normally, you'd want to be careful when removing rotors, but since these are going in the recycling pile, they were removed with a good whack from a mallet. A note on the backing plates: In stock configuration, brakelines would be supported by them en route to the calipers. But new brakelines will go from the diff housing straight to the calipers, so out go the backing plates and old brakelines.