Vinyl works well if you can find a sheet that matches your paint fairly Jo-Ann Fabrics and Michaels Crafts sell single sheets of vinyl that hold up in the elements. My wife has different sized hole punches from 1/4" -2" (bought at the same stores) and I used those to make the circle bandaid like covers. Did the same thing to my buddy's sports car who removed his wing and wanted to plug the holes to keep water out of his trunk. Held up to car washes. A little less noticeable then the plastic tabs but it's your vehicle so you will always notice what other people won't.
