If you look closely Alex, the design of the spokes do go out to have good caliper clearance, but the face of the disc that attaches to the rim is flush with the mounting hub. I call this real lip.

Other wheels have the face of the disc like that too but they mount farther behind the mounting hub creating "more" lip. It still looks cool but not as dope.

As for the GT-P', you have to remember that because of the design of the wheel, you loose about 10mm of lip.
As for modifications, be prepared to roll your fenders like crazy!

We found it best to score the paint with a sharp razor blade and roll with a bat till that fender lip is flush with the outside fender to give you the extra room. Paint still chipped but not as much and to cover it up, we painted it with some rust coating and applied touch up paint on the outside where the paint chipped. My paint is old and stuff so I didn't mind.
Good luck.