Re: Can I keep my stock CD changer and change out the face?
Short answer: no.
Longer answer: mirroring the display from your smartphone is technically Sony's feature, at least if you literally mean MirrorLink. Sony eSupport - Compatible Devices Equipped with MirrorLink™ Feature
Your phone is not supported by this feature, plus it's pretty old in terms of smartphones.
I don't know what you mean by "the head units that can be detached and still function".
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