I just bought and installed a Flushmount spoiler off eBay - painted and shipped for $130. I have 2 issues.
1) the two outermost holes I drilled are in an area of the trunk lid that's obstructed by the substructure so when i went to put the screws in, I lost them in the trunk lid. Fml.
2) the spoiler bounces. I've been told to remove the rubber washers that were provided and use 3m double sided tape and the 4 remaining screws I have. Does anyone have any better suggestions?

 

I got one for about that from ebay, I didn't use any washers from what I can remember, or any tape, just screwed all 4 in nice and tight and used the rust inhibiting gel it came with. I would get a telescoping magnet stick and get those screws and then screw all 4 in nice and tight.

Good luck

 

ive installed one of this flush mount spoilers on my friends car, they also bought off ebay, (i dont reccomend doing, since those parts dont always fit right just like theirs didnt on the underside.) but non the less i only drilled out the 4 center holes, (since i knew from past experince of putting the low lip spoiler on my past 2011 TC you cant reach them from the inside of the trunk). but we got 3M double side tape cause thats what OEM uses and so used the little rubber washers. but put tape all over it and tighted the 4 bolts as much as i could and it seems good so far.. the sides seem to have a tad of a gap since they dont have the screws in them. but its held down by the tape at least.

 

The dealership even screwed up my install. 1/4" gaps or more on the back end of the spoiler. Turns out some of the spoilers are warped from shipping. They ended up bringing in 3-4 spoilers and having a body shop perform the install to make it look factory installed.