Rick, quick and easy would be a piece of stainless steel. Maybe a piece that has the diamond pattern for a better look. You could try HD or lowes and see if they have some that is close to the size you need. You might also try a scrap steel outlet. They normally can cut a piece to the size you need. You could glue it on or use velcro. I like the velcro, that way you can take it off to clean behind it. Just a thought. Bob