The short answer is that if you pull the factory head unit, then you will also need to replace the DSP amp and speakers. The DSP amp will only work with the factory HU. Likewise, the speakers are matched to the internal active crossovers of the DSP amp.

Plus, if you replace the HU, the new HU would likely have iPod and aux inputs, so that would obviate the need for the PA-12 as well.

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2000 E38 750iL Highline Edition, Upgraded with the lastest 2006 X5 Electronics
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