Just a brief update, Ive today discovered that my iPhone connects automatically to the CarPlay screen and also the Morgans MusicStream bluetooth device. This allows me to not only control my music library, radio, messages, maps guidance etc.,via the larger touchscreen but also listen to them all through the cars built in speakers.
As I hate connecting plugs all the time, I'm going to relocate the iPhones MagSafe charger onto the metal box (technical term) sited just above the passengers footwell. This will keep my phone charged and out of sight whilst everything is cast to the larger display.
Incidentally, whilst looking for a suitable location to mount the thing, I came across another half hidden twisty dial near the overseer switch to the right of the steering wheel... I was today years old when I realised I can now turn up the brightness on the instrument display! hopefully no more squinting to see the digital display in between the steering wheel.

Lastly, whilst fidgeting around and removing the MusicStream box (velcro'd in position), another female connector block became visible. It's nice to know there's an additional 12v supply there if needed.
Cheers