Pretty much.
It uses the two holes on the trunk lid (I had to very slightly elongate one with my die grinder) and at each tip there is a screw that goes in to the fiberglass with enough of the head sticking out that it catches and slides in to the front slot on the glass.

Issues with the wing:
I had to remove the middle and rear brackets off the glass. No big deal with a grinder wheel and a couple other tools. Just be smart and gentle and watch the heat build up. The brackets were acting as a fulcrum and preventing the rear of the wing from fully contacting the deck lid... Easy fix.
The "shroud" for the 3rd brake light didn't fit all too well afterwards without some modification... So I'm just gonna leave it out and come up with another idea for a 3rd brake light... I'd like to mount a little LED strip light on the rear edge of the wing, but that would require a couple holes in a new wing and fishing the wiring through... And I'm on a time crunch to get the body done now as all my LS swap parts are almost here.

I got my wing from them as well and it was a good fit. It mounts with a couple of screws on the tips that slide into the top clips and then two bolts up through the rear deck where the factory spoiler connects to it. Might take a little finessing, but it looks like a OEM piece once it's in place.