Now you need to file and sand the Carbon fiber (refered to as CF from now on) facia till you have an exact fit in the bezel. A fine toothed metal file works well to rough it in and then and finish with 80 grit sandpaper. When you think you've got the fit correct put the CF facia in the bezel and then put the original stock facia behind that and use some clamps to hold everything. This way you'll be able to check for a more exact fit.
The center area by the steering column can not be taller than the original facia or it will be very difficult to install the completed panel in the dash. It is easy to end up with the center of the panel too tall and have it still fit in the bezel when you are fitting it without the original bezel in place because of the flexibility of the bezel. If it is too tall there it will also be difficult to pop rivet the completed assembly together later so be sure the CF panel is exact.