fronts are completely different from 02-05 wrxs and ANY sti. sti 04's are different from 05's. the bar that stays the same on 04-05 sti's is the rear, and that one is also different from wrx's. the 05 front sway bar is different because of the stock antilift kit.
here is a thread from like a million years ago saying all the same stuff.
http://www.iwsti.com/forums/showthread.php?t=26301
the newest biggest whiteline bars are the 3003x and the 3006x. the latter being for the 05. they are 25-28mm adj. they barely fit through the body mounts with bushings in there. you cannot get these for the wrx. these are bars made only for the sti. sidenote, they are solid bars. which are alot stiffer than a hollow bar, 5mm thicker.
it is my understanding that once you change the way the front bars mount to the car, you get into an autox class that noone wants to be in. this is explained in the thread above.
i know jack shit about autox, just barfing up knowledge i have read places.