i just bought a used car that came with a some sony hu, and i wanted to install my old pioneer, it's an mp3 player so it makes everything a lot nicer. anyway when i took out the old hu, i noticed the plug with a bunch of different wires, including the speaker wire, was different and doesn't fit into the back of my pioneer. What do i do? i didn't take out the clip from my old car and i traded it in so i don't have access to that anymore. did i just make a big mistake?