Well that was easy!
Mr 2 went to bed early so I had some time after dinner to swap the new head unit in.
First up is removing the old head unit, the centre vents (the worst bit of the exercise), and the lower console bracket, so that I could install the HVAC relocation bracket.
Console bracket out.
How does so much debris get into a sealed area!!!
The car had had a Parrot bluetooth unit installed, which never worked properly for me, so that had to come out. I was a bit worried about how the wiring for it might have been done. The wiring harness had in fact been cut to put the Parrot unit in series. Fortunately it had been done well and I was able to just unplug the Parrot harness and plug the OE harness back together. I'll tidy it up further in the future, but for now I've wrapped it with fleece tape and packaged it up.
I then swapped the switch strip and cigarette lighter across to the HVAC relocation bracket (photo taken before swapping over):
The Xtrons unit comes with an ISO wiring harness and it makes it ridiculously easy to connect the head unit. Just plug it into the Xtrons and plug it into the car harness and that is literally it. Everything just works. The ISO harness comes with some other tails for other harnesses. I intend to remove these connectors I don't need at some point in the future to tidy things up further, but before I do that I'll just run the unit for a while and make sure I'm happy with it.
Once I'd done a quick test to make sure functions were working I put everything back together, and voila!
It works.
As others have noted the dash trim doesn't sit quite right. This appears to be because the clip is built into the Xtrons (see below) and it seems to be slightly too high up - a quick go with a file will fix this I think - again will get back to this over the Christmas break.
Initial impressions of the head unit?
Ridiculously easy to install and get setup - you get a ton of wiring harnesses in the box and it seems intimidating. You only need the ISO one and it's entirely plug and play, no tapping to do, no extra wires to hook into, nothing. Just plug in the additional things you want (GPS, Wifi Antenna, etc. I didn't bother with the USB ports, 4G, etc. as I won't use them).
The unit is FAST. No delays anywhere, the UI is fast and responsive.
CarPlay seems good so far, I connected my phone via bluetooth and it just worked.
The real test is going to come over the next few months as I see if it reliably works well and quickly, or if there are gremlins. Promising start anyway, will provide an update in a few weeks once I've used it for a while.