Don't panic!
I got a s/h rear boot lid and genuine wing for my Hawkeye last month.
Just to prepare I've took the WRX type rear spoiler off my car and have to say it looks sort of quite nice without one on! Well, different.
Didn't realise the intracacy of the genuine spoilers.
The WRX one has only four bolts, but a single plastic fitting and clip lug mount on each side too, plus the wiring for the LED light.
You often hear ads for the STi style spoilers saying you can use the holes and perhaps drill a couple more for security....let's just say this is why I have NEVER seen a replica fit properly.
The proper STi has a pair of the clips on each side and a total of 13 studs and nut fittings. Plus the six bolts that join lower to upper- and two of the lower fixings are actually ends of the wire lanyard that goes up and over through the upper spoiler. Over 70 parts in total to a genuine spoiler.
The torsion bars in the boot are bigger too, as the WRX spoiler weighs next to nothing, BTW.
Just need to save up for the roof vane now.