[wrenchnride247]

A can of oven cleaner, or engine degreaser, wire brush, and the local car wash is the first step I took. If you have someone with a parts washer then that can do the same thing. Once all the "bulk dirt" is off you can use different types of wire wheels in a hand held drill to clean them up to the finish you want. If you want them to stay clean get some "rattle can" clear coat , and spray a coat or two on them (eastwood company makes a good clear called diamond clear that won't yellow). That way dirt can't stick as easy, and you can hose them off easier .