I would love that this would work. I don't share concerns that The Max raised about tapping into critical systems, a delay in the air con coming on would not be a deal breaker.
Would it work as is, is the question. I looked at the Grom Audio Vline solution and after sending them many photos and a lot of back and forth they said their solution will not work with the Japanese head unit. This is a little different as it completely replaces it, but I would be concerned it would not work with the Bose setup.
If someone has a spare 1k and wants to give it shot I'm sure many people would be very keen to hear the results as it looks a lot better than the tack on android setups that end up costing the same amount.