I bought the necessary wiring harness off Eddie-NL who's support and guidance was needed!
The install was slow and tricky, especially the interior mirror plug disassembly, which I suggest you look at first as I couldn't get my head around it's disassembly but Ed advised me how or it would of end up f**ked for sure!
This plug took the majority of my install time and the need to have a fine metal draw rod to pull the new wires into it from the roof lining.
I did find a how to after the event which would of greatly helped on a Skoda site which I'll look for.