Don't know much about stereos but a buddy had these in his truck he wrecked and I bought them. Pair Polk db651 rear. Pair Eclipse SC6900. It actually seems like these will fit into my 06 CC. He has 4 Eclipse SC6900 I could buy and use all 4 of those instead of the 2 Polks. One of u stereo guys tell me what's better. I'm assuming I can fabricate a plate for any of these in any door.