Factory amplified systems generally sound like shit with aftermarket decks. Factory amps usually see a high signal, and factory speakers and subs usually play at odd ohm loads. Not to mention, I seriously doubt you're going to get your factory sub/amp to even work. Steering wheel controls can be intergrated usually using a device such as a SWIX, but I'm not sure in your application. In your case, it might be better to just stick with the OEM deck if you really like the way it sounds.