A bit of a side update on this. Today, I attempted to install a 2019 Facelift speedo into a 2015 pre facelift, facelift car.
The car has traction control and tyre pressure sensors so I thought it would work properly.
So, it works, however the car it came out of clearly had hill start assist, which this one doesn't that it comes up with an error on start up which then goes but because the facelift stereo screen is where you adjust the time and date, you can't do it on the menu buttons on the speedo
Lastly, as its out of a later generation car, the proxy alignment won't work so the mileage is flashing.
She has at least got an LCD display at long last, so I am going to change the LCD in her original speedo.
So, word of warning, it's not just the colour speedos that aren't cross compatible, the standard orange ones are not compatible either.