Appropriate Wheel Offset for 18" Wheels?

MuuMuu101 said
The bbp axle flanges are about 3/16" to 1/4" thicker than the sbp flange. So there's a potential 1/2" total. I'll measure again to make sure I'm not crazy because this is boggling my mind too.

I would disregard that axle flange part, because my measurements are coming off of BBP axles with 11x2.5" BBP brakes...