I think that is a common problem caused by big feet. Because nothing connects to it and it's not visible, unless you crawl under the dash, I would just smooth it off. If you're trying to make it concourse correct, or showroom fresh, I would try patching it first, by smoothing out the broken end and use a good adhesive, like epoxy or Plastic Bond, to attach a patch to replace the broken section. You should be able to find a piece of strong plastic, like ABS, that is the same thickness.