this is an example of my rear setup im currently using:
Volk CE28N
18x9.5 +28 offset
265/35/18
negative 2deg camber
This rim resembles the 1st illustration on the left showing positive offset. Since the illustrations below are exaggerated a bit to show the differences, it has a curb appearance of the center illustration even tho my rear setup is positive.
These are pics from the back of the rim showing coilover to rim clearance. The clearance between the rim and coilover is about 30mm total.
(be sure to leave at least 4mm open space for things to move, otherwise you will rub)
this is how the rear looks with this setup. with minor lip massaging and -2deg. camber adjustment, the wheel tucks without major rubbing.