Figured i would help a few people out. Some are the edge of buying this spoiler and not sure how the installation is. This is what i put together so hope it helps.
Since 5 holes have to filled on the trunk lid itself i purchased another trunk lid for this reason. I stripped it down and removed the stock g8 spoiler "which was a pain in the a$$".
You can get the spoiler here.
http://www.pfyc.com/pc/G81029/G8EXT/...8+Spoiler.html
Parts from PFYC
After spoiler is removed you will find these holes that will need to be filled in.
2 new holes will need to be drilled 1 on each side. I used a 5/16" drill bit and drilled out the existing hole to help with bolt alignment.
On the bottom side of the trunk lid you will see a hole that was filled originally.
New bolts in with spoiler
Test fit and tighten down.
After complete
The Holden/Euro Spoiler from PFYC.