Hey Guys,
I'm at the opposite situation.
I'm about to buy a rear Spoiler and I'm not sure about it, because so far I have seen 2 models one with 2 screws and another one without them.
One seller say to me easy take it to a car-shop and the will make 2 holes on the fiberglass of your car and then they will screw the spoiler.
For Mini Cooper 03 07 R53 R50 R51 One Cooper 's' FRP Fiber Glass Rear Spoiler | eBay

The other seller (spoiler without screw) said to me to use a special glue for it "BODY KIT SPOILER FIXING ADHESIVE GLUE CAR BODY REPAIR"
BMW MINI ONE COOPER S R50 - REAR ROOF SPOILER - TUNING-GT | eBay
[ BODY KIT SPOILER FIXING ADHESIVE GLUE CAR BODY REPAIR | eBay ]

The question is that my mini doesn't have any holes for a spoiler.
Has someone before, how did you do it?
Thanks your the advices, cheers.
Rene.