My brother has a 2009 4x4 with 2" levelling kit and 17x9 wheels +18 offset 5.71 backspace, and 285/70/17 a/t tires and 1.5 bushwhacker pocket flares. Tires are close to flush but not quite there. Would a 12.5 tire make it flush or does he need different wheels with lower offset and b.s? If wheels what b.s. and offset will help? Thanks