New to the S63 AMG world!

Anywho, just bought a 2008 S63 AMG Designo so getting my feet wet in a whole new realm. Car is arctic white and completely stock, but I cant leave anything stock, so looking for advice on wheels to begin with. Non 4-matic.
I've googled to the end of the earth but cannot definitely find what the stock size wheels are. I would like to go staggered possibly, but cant find much info either on what fits? Currently has 20" AMG 5 spokes. Any suggestions are greatly appreciated. I dont necessarily need to go staggered either.





