I had et-15 18x10 225.40.18 on 30mm overfenders with .9 degrees of camber..
so you'd be 5mm further in, due to offset but 20mm further out due to tyre width (265 minimum I would say)
even with 4 degrees of camber (working on the rule of thumb that on an 18" 1 degree = 6mm at the top of the wheel, that would *just* work, but thats silly camber on the rear