When I worked for a bumper plating service here is St.Louis (Many Years Ago) they experimented with plastic welding. It worked good on salvageable bumper cores. There is a web site that has information on identifing plastics. www.urethanesupplycompany Check the how to section. I hope that helps you out. Also let us know when you go into bussiness, I'm, sure we could send some work your way. My quick fix was to paint the radio face with duplicolor black trim paint. It actually blends the radio in, and unless you are looking for it, you can't notice the missing piece of the bezel.
