I would like to hook up an after market deck to replace the non-functioning becker in the 1988 420sel. I would rather not disturb the crossovers that these speakers have. Is that why you choose this way of installation rather than powering the speakers with the new h/u? If I have only four speaker outputs on the new h/u and the car has six speakers how will that work. I am really bad when it comes to electrical. Thanks