Ok, i just purchased a head unit for my car. Its a sony L550X. All the wiring and everything is as it should be however there is a large black plug with 5 connectors in it. I had the stock CD player, stock casette player, and regular AM/FM radio with the listening position thingamabob. What do I do with the black thing? Im comtemplating ripping all stock amps and crap out and just installing my own equipment.

 

Start over. Rip it all out. It's easier!