If you are handy w/ powertools, and feel bold enough to drill large holes in your brand new tC, this how-to is right up your alley.

Difficulty level: 2
Install time: <1 hr

Note 1: The installation kit is purchased seperately and consists of a Mylar template and the installation instructions. It's a little pricey, like $45 (ouch), but is invaluable in making the installation go smoothly. All installation hardware is included w/ the lip, not the install kit.

Note 2:
This How-To does not follow the installation instructions exactly as provided w/ the install kit. Some steps have been substituted or order changed. For use as a guideline only.

Unroll the template and align the top corners w/ the hatch. Attach w/ masking tape in the marked locations. Take care in aligning the bottom edge, amking sure that it is level.

Using a center punch, mark the center point for each of the four holes to be drilled using the template as a guide. The template is pre-punched and marked at these locations. Remove the template when finished.

Open the hatch and remove the two screws located beneath each handle.

Gently pry to remove the two side and top mouldings on the underside of the hatch and set aside.

Using a panel removal tool, remove the main panel on the underside of the hatch and set aside.

Close the hatch. Using the four center punch marks, drill 1/8" pilot holes at each mark.

Drill a 3/8" hole at the left of center pilot hole. I used a Uni-bit, or step drill for these steps.

Drill a 5/16" hole at the right of center pilot hole. This hole is slightly larger to allow a margin of error.

Drill a 13/16" hole at each of the two outer pilot holes.
Clean the entire surface with rubbing alcohol and a soft cloth to remove any dirt or oil.

Run a small bead of silicone around each of the four holes drilled.

Insert the two white sockets into the two outer 13/16" holes. Align them horizontily and press firmly into the hole.
Remove the red protective tape from the spoiler to expose the adhesive surface. Be sure not to touch the surface to ensure good adhesion.
Holding the spoiler on the two outer edges, align the two center bolts and center the spoiler using your fingertips as a centering guide. Sorry, no pics...didn't have enough hands, hehe.

Once properly aligned, use the palms of your hands to press the two outer edges firmly into the sockets at the same time until it snaps into place. Press firmly around the enire perimiter of the spoiler to ensure proper adhesion of the tape.

Insert and tighten the 10mm nuts to the two center bolts from the underside of the hatch. Replace the main panel and the two side and top mouldings on the underside of the hatch. Replace the two screws located beneath each handle.
Ta da!! Your done!

Rear view:

Side view: