Thanks for all the suggestions. I tried Gordon's and found that the grommets became really heavy, comparatively, once I trimmed and filled the hole.
Great idea, just didn't execute it well.
I went to Lowe's and wandered for about twenty minutes thinking about what would work. As I was meandering through the flooring section I noticed the flexible rubber baseboard material. It's light, flexible to go around a curve, would take paint and could be applied using the same silicone that holds it to a wall.
So, about $10.00 later I was on my way.
Used the grommets as a template and cut out four matching pieces from the baseboard material. Sanded, primed, rattle canned three coats of body color matching paint I had made a couple years ago, finished with two coats of spray clear coat.
Taped off the area around the holes to guarantee straight fit, applied the adhesive and stuck them on.
If I want to go back to bumpers, these should be easily removable and because of where they are placed, the bumper bracket grommets would cover any damage.
I have seen similar bumper bracket covers on other cars, including replicas and steel cars as well. Really simple fix. Not to everyone's liking but I am moving inexorably towards a minimalist outlaw look and this will work for now.
Fun little project.