Grille ornament

Prior to K-GAP making the first reproduction in 1980, I and others would spend hours with tiny dental pics and bits of VERY fine sandpaper cleaning the old paint from the inside of the medallion. The alum. silver has to go into the "chrome" areas first and then the red paint all from the craft store. You'll never get the chrome as shiny as factory vacuum plating nor the candy red as brilliant as the factory placed coating. With your paints you won't need the gray backing that was sprayed over all to keep it in place. I found that daubing whole milk on the white triangle multiple times gave the best translucence for the light behind it.
If you've got nothing but time on your hands and a steady hand to boot, you can create something that at best will look half as good as the currently available reproduction which is worth every penny of its price.