8.5 in front you need an offset of about 28 / 30 to have it flush with the fender. but might rub when you use a wide tire ( 245+ ) or rub when seriously lowered.
offset 35 would look very nice.
9.5 in the rear would need an offset of about 24 to be flush i guess give or take a few mm.
offset 35 would sit about 10mm from the fender , which would look good !
you defenitly not rub the fender .
i have :
8.5 +30 up front and a 235 tire , its close to flush .. looks aggresive and i have it lowered by 30mm
for the rear i use 10.0 +34 and 265 tire , its about 3 - 5 mm from flush looks good , the rear is also lowered .. not sure if its either 25mm or 30mm but it defenitly isnt rubbing. offset +30 would probarly fit w/o any problems though.