OK, I posted this on NASIOC (http://forums.nasioc.com/forums/showthread.php?s=&postid=6118484#post6118484) today and it was suggested I put it here too. This is my first Scoobymod post, so please bear with me. I think I am only supposed to do one picture per post so this might take a while...

Here goes, and mods, feel free to edit as you choose, I'm just trying to help with this mod.

BEFORE YOU START:

READ THIS WHOLE THREAD!
I am not responsible for any holes you cut in your bumper!
MEASURE TWICE!
READ THE WHOLE THREAD AGAIN!
MEASURE AGAIN!

You will need a sharp cutting tool (I used a steak knife) and a screw driver. The measuring consisted of me holding my splitter up to the bumper and eyeballing where the hole should go. This worked well for me, but make sure you cut the holes in the correct location. If you make the holes a tad longer then the tab it helps.

For the side splitters to go onto my wrx, I cut 3 holes per side for the tabs to go into. Here is a picture of the 3 holes:
http://www.pbase.com/image/18655095/original.jpg
To cut these holes I carefully lined up the side splitters with the car to determine where the hole should go, and then used a sharp knife to cut the holes. It's more than a slit (thicker). There is actually a little bit of plastic removed...

I then "adjusted" the splitters to be used on a WRX instead of an STi. In this picture you can see the 2 splitters. The top one has had the white tabs removed, as well as the black plastic pieces that held them in place. To do this I used the same sharp knife. (Actually a steak knife):
http://www.pbase.com/image/18655169/original.jpg
You can also see the hardware I used to install these. The 6 bolts and clip nuts are in the picture.

You then pop the 3 tabs on each side into the hole you cut in your bumper, and use the metal tabs and bolts that came with the splitter to bolt the rest up under the car (as seen in the previous picture). That is the easy part. The only tricky or hard part of the whole thing is cutting the holes and that's becasue you have to cut a whole in your nice car...

Here are some finished pictures:
http://www.pbase.com/image/18655212/original.jpg

http://www.pbase.com/image/20513206/original.jpg

http://www.pbase.com/image/20513168/original.jpg

http://www.pbase.com/image/21521986/medium.jpg

I hope this helps! Remember this is my first post here at scoobymods, so I hope I put everything together right. Also I didn't ttake pictures specifically for a how to thread, so I will do better next time, but I happened to take these and they are good enough for this thread to be helpful. Some people have put theirs on with double stick tape too, and skipped some or all of the hole cutting, but this worked well for me.

Good Luck, and as Kastle will point out... I (or he) am not resoponsible for holes cut in your bumper in the wrong place!

MEASURE TWICE!

Ben