the offset his getting is pretty low +35 or +30 on a 9.5? cant remember now but mine is 9"+22 and shit flush with my guards
Boxerbeast had GTR rims and they were 18x9 +30 which were rubbing bad on his rears lol and swaped back to gmax
and also you cant roll the rear due to that extra lip which is only on the STI, the wrx are fine
put it on with the 225 tyres and smash in some camber then see how you go but I dont think you need to hack into the rears imo....given that it clears the front brembos KEK
wish I had 34 GTR guards