If you're talking about the defrost vent itself, there was a TSB for this and a repair kit that Ford came out with. It pretty much consisted of the vent being removed and a different style screwed down in place of it. I know this was for at least the 2000 Contour, and probably the '99 also.
I think it's a pretty big job if you have to do it yourself, as the whole dash needs to be removed.
