@fazi123 it's pretty easy to do the MDI install I did it on my GTI. Once you have the head unit section sorted, if you take the front ashtray out you can feed the wire down the back and run it along the side of the centre console.
Once you get to where the MDI sits you can feed it in underneath. And the rest of the wire you can tuck it under the centre console. All this without taking any of the rest of the armrest etc out. Now I've done it is kick myself if I had to pay someone to do it once I realised how easy it is