That is cracking service , hopefully mine is not far behind, I will wait for your detailed fitting instructions 
Lots of fitting advice on the other p/n thread but for what it’s worth I marked each side of the spoiler with masking tape then took a long tape strip vertically down from the satnav sharks tooth on the roof over the spoiler to the rear hatch, cut the tape at the top and bottom edges of the spoiler and got a perfect reference from there.
For the life of me I can’t work out how to post images and have given up. But take it from me.... this spoiler on the back of an Indium Grey car is a truly lovely thing. So subtle, so classy.