Depending on the current condition, there are several steps to restore them.
Assuming no cracks or damage, very mild blasting of the centers is OK-just not silica grits or aluminum oxide. I've used emory, bronze wool, scuff pads and grades of Nuvite polish to get to full polish-from most aggressive to least in order. Test small area to find the least-aggressive to start with-never use more grit than you have to. The Nuvite using the 'C' grit to start and 'S' for final high polish is excellent once you have gotten through the porous oxidation. Use their white application pads-excellent.
You can stop anywhere along the process if you want a satin or dull finish. Spray the centers with Duplicolor clear wheel acrylic-no paint or powder. DO NOT clear the machined rims-heat and brake dust will attack it under the clear. Just occasionally Nuvite them. These are 23 years old.
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