Originally Posted by Six7One
You can get some studs to resolve that. Or you can cut a few extra screws to make aligning "pins". Just cut the heads off and screw them in enough. Wrap them with tape to prevent scratches.
Thats essentially what I ended up doing. I put 4 dowel pins in the holes and put a dab of red paint on the end, positioned the spoiler where I wanted it then set it on the trunk. Once that was done I had 4 dots on the trunk, verified there position with a tape measure, and drilled them out.