Porsche does not prewire a car for anything. In the old days we would buy the Becker 2260 changer and in the box was the cable from the radio head to the changer. This changer is identical to the Porsche CDC-3 changer. The 2660 changer has been discontinued, but there is a replacement that is a bit smaller so it is not a direct fit on the factory mounting bracket. You can find the 2260 changer on ebay or get a refurbished unit from Becker. If it does not come with the cable then you can buy it for $75. Jeff
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