Cleaning an aluminum engines (LS-1) exterior ?

[Tim john---]

Good day all, I have a 2004 GTO LS-1 engine for my project and the engines aluminum is stained, blotchy, dark spots etc.. I have washed it thoroughly, no grease, no oil, no debris. Engine is complete ready to install but is there something that I can use to pretty it up better. It is just weathered. We use to use a product called "Renewsit" on the farm semi fuel tanks that I have not tried yet, do you have any additional reccomendations or processes. Thank You. Tim john---