I had a look at this in depth.
If you want OEM Bluetooth you need to buy a Bluetooth module, and microphone, there's a retrofit loom that's needed too.
You can send the tv unit to the uk to be changed over to digital and they can beef up the amp at the same time if you send it over. Not cheap though
A MK4 nav should be plug and play for you and if you get an intravee you can integrate an iPod
I'm going to go down the NBT route with mine so could sell you all you my MK4 and intravee, or you can just try them and see how you get on
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