That grille work has inspired me to take another look at the nose of my Olds. If I could make a rolled pan to replace the bumper, and use a similar method to yours in order to turn the opening into a symmetrical oval instead of its current sad face...
Well. Attached is a cropped and scaled piece of a
1280x960 image of a 2005 Holden Efijy Concept car that has a nice look, IMO. Too bad my fenders are not as fat as that one's or yours.
Thanks for posting all this info!