I currently have a fully custom stereo 2 ddx sKars in a 4th order blow through the rear seat center armrest one a CAB 2000.1. All Focal interior speakers with and extra set of component in the front doors running off a Polk Audio 4 channel with a DQ-61 Audiocontrol concerting my stock signal into the amps. Spent some time researching this before I did it. Stock head unit. All the sudden a few days ago about 15 seconds after being in the car I lose all mids and highs. Subs still work but that signal to the processer is pulling front the sub amp as the rest pull from the stock head unit. I just want to do a Double in it now land completely eliminate the stock audio system all together. What harness do I need to make this happen. They are expensive and I just cannot lock down which one it is. I would like to retain steering and I Drive is possible but if not I really don’t care. Can someone help or share what they did. Just a basic hifi set up is what came stock.