Has anyone tried to protect the plastic door sill area? I'm looking for a way to prevent the scratching and scuffing of the plastic that occurs when passengers (and my dog) move in and out of the side doors. I was thinking that some adhesive non-slip material, the type that is placed on steps and the like, would be a good choice. However, I'd like to hear if anyone else has tried something that works better or has any ideas. Thanks in advance.