Kiiz,
As the rear part is 2 piece (whole kit is 6 piece - 2 front and 4 rear), it doesn't get in the way of the doors, one piece stays on the door and one piece bolts to the back part which allows the door to open fine....pulled this info from the ABW website...
ABWMOTORSPORT SUBARU BODYKITS
I'm assuming one would need to cut existing flare/guards then fit those?
I wonder who is going to be game to try 18x10.5+ wheels with flares...not me lol