Whit....use the stock head unit and power amp a few thousand watts from the stock amp in the trunk. I have read soooo much on people that have done wonderful things with a total redo that has taken weeks and resulted in astounding sound systems. From all I absorbed I would not want to axe my stock system but add to its fury with an amp and maybe some replacement speakers. Once into "the goods" your at your own mercey.
95 E34 530I V2.37
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Those who make peaceful revolution impossible will make violent revolution inevitable.
John F. Kennedy