You should start by cleaning them first. Use a wire brush & mild detergent to scrub off dirt and grime. Then apply some degreaser to help loosen up the metal. After that, wipe away excess grease with a clean cloth and let dry completely before proceeding.nUse paint thinner to remove the top coating. Then start sanding with 200 grit sandpaper, then go for wet sanding & use finer grit up to 1000. In the end, polish the wheels with aluminum metal polish.