I'll admit to having thought about doing it, when I bought it. I looked for the thinest and lightest diamond plate material I could find. I didn't want to add a ton of weight, particularly to the door. I got over the idea, for the time being. I have been pulling the trailer for about 5 years, and have no rock damage.
It does get dirtry on the sides, and some high heat from the exhaust in re-gen. I might re-think it after you post a parts list and instructions