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Any chance I could see a screenshot?

I don't seem to be able to select the source for my vehicle. Or any other for that matter.
 
I believe you need to first go to Settings > Bluetooth and connect to the Bluetooth devices from there. Once it is connected, it should show up as possible AirPlay options in places where you have AirPlay controls.
 
Any chance I could see a screenshot?

I don't seem to be able to select the source for my vehicle. Or any other for that matter.

You have to pair your phone with your car's bluetooth system before you can change audio sources.
 
Yep pair first in Settings -- Bluetooth
Then go to Control Center and select the AirPlay options -- your stereo should be listed there.
 
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