I took my 1968
29' Streamline Empress up to Gilroy, where the MetalWax folks are located. I forget the guy's name, but he did a phenominal job of cleaning that anodized aluminum. When I got the trailer back, it looked a million times better.
I use MetalWax religiously on the diamond plate on my truck, and it looks great. You want to use MetalCleaner first, though.