I helped by buddy with a tj paint his, pulled them off, cleaned them really good, wet sanded them, and coated them with bed liner in a rattle-can. Duplicolor brand I believe, but the brand shouldn't matter too much. The stuff was from auto zone and it cost maybe $25 total for three cans. His fenders looked a lot like yours do in the picture above. I don't have any before pictures, but here are some right after we put them back on. The fenders have been shown the trail after we painted them and they've held up fine, we actually ended up doing his door handles, gas cap and surround, and his bumper end caps. It made a huge difference to freshen up the jeep. It's been quite a few months now and none of the sprayed areas have shown noticeable degradation. Go for it, just take your time applying it and letting it dry. Maybe practice on something first with the spray, because it is a little bit different from spray paint. Post up pics when you're done too! Good luck!