Not wanting to guess by looking at your pics, but what's your rear D height? Looks less than 1", or is your camber strut bracket non-stock? One reason I ask is that I had thought I'd worked out that a 285/40ZR18 should clear on a 10x18" w/5.5" BS, and I'm wondering how much your ride height is contributing to the slight clearance issue you have.
BTW, I don't see anything aesthetically wrong with thinner fender lips as long as you follow thru and make them the same all around.
If your shark can't pull at least 1 "G" you've got more work to do. [Only registered and activated users can see links. Click Here To Register...]