Trunk trim
If it's anodized aluminum see if you can find someone who can remove the anodizing. Then you can sand and buff to your heart's content. Aluminum oxides quickly, so it's important to get it re-anodized in fairly short order. The trunk panel from my 66 Dart GT was extra bad and I couldn't find a replacement. This is the process I used to restore it. While aluminum can be buffed out to a chrome-like finish, anodizing will make it look a little milky.
If it's anodized aluminum see if you can find someone who can remove the anodizing. Then you can sand and buff to your heart's content. Aluminum oxides quickly, so it's important to get it re-anodized in fairly short order. The trunk panel from my 66 Dart GT was extra bad and I couldn't find a replacement. This is the process I used to restore it. While aluminum can be buffed out to a chrome-like finish, anodizing will make it look a little milky.