I was about to post a question about this. I just put mine just as the instructions said. And I have the gap also. I'm going to try trimming some of area around the outside tabs to see if I can get it tighter.

 

a SMALL (less than 3.5mm) gap is normal... If it's so big that it's obvious, then its probably too big... Really, you just need to push the ends of the spoiler on as far back as they will go, nice and tight, before you press down to stick the double stick tape... Cause really, it's placement of the top ends of the spoiler that determine that gap, and the only thing holding it in place is the double stick tape...

NOW, if you drill, then the placement of the holes will affect the gap as well, which is not good since if you don't drill the holes for a perfect tight fit, you can have a larger gap than desired...

BUT, the holes to drill are pre-marked on the stock bumper, so really, you should be conservative and drill them exactly as marked or just slightly higher so that the spoiler fits EXTRA tight...

FINALLY, there really is no point to drilling... Just makes it permanent and is more work...

 

OK, so I hate the fact that you guys will be in Vegas and I wont...

Anyway, I'm not sure if you guys have seen this or not, but here's the Installation guide from Factory Service Manual:

 

...and here's pages 6 through 11:

Javier

 

You have no one to blame but yourself...... (<----btw that's *rolls eyes")

 

mine has gap as well...I guess lighter color cars shows more oppose to darker color cars. No mattr how hard i push it, it seems that the last clip near the curve doesnt seem to want to snap in. Maybe I forgot to snap that little plastic piece off the spoiler? I saw in the instruction that you need to cut off a little plastic piece by the curve? probably remove it and redo it over again.