RNS510 Retrofit
By far the hardest part of the install was running the mic cable. You'll already have that done, so the rest should be quite easy. I'm not sure what all the differences in features are between the old unit and the 9w7, but if one of them is voice control is you want to enable the mic button on the steering wheel (assuming it isn't already done) you'll need to make the necessary changes using VCDS.
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