Looks like there is definitely a shorter shoe on the right side of the pictures to me. Is it possible that there is a spot on the backing plate that the shoes rub on that has a burr, or is just worn funny that the shoe is hanging up on? Other thing I notice is the weird little oval spring on the bar that sits under the brake cylinder is missing a few coils. Not sure what this spring does, but do know that they do not come in any of the spring packs that I've seen. Nappa has them, would have to look up the part number, pretty sure I put it in one of my old posts somewhere, also have half a dozen at home I stocked up on. They were a buck or so each.