I'm starting my swing away tire carrier and wondering where to get a latch that holds it to the bumper when closed. I'm not even sure if you call it a latch, edgeekate me. Also, where to find the thick plastic plate that can be bolted to the bumper to help guide the swing away onto the bumper when it is closed. Once again, I'm not sure what this material is called, "plastic" may be too general of a term. Thanks!!