01 SOM SS

Ok guys i've searched the forum and still haven't found an answer to my question. Ok I plan on purchasing a Pioneer AVHP-6600DVD and for now i want to use it with the stock Monsoon system. From what i understand the pioneer comes with wires for the front, rear, and a sub speakers. How exactly would i use that to wire up the Monsoon. One of my friends told me I would need some kind of converter box. Is this box the OEM-1? Also on the website where you purchase it from its asks if its a Pioneer 12, 14, or 16 pin, does anyone know what this HU is? Or is there another way to wire this. Thanks guys I really need your help.