ET25 wheels will need 8-10mm spacers to bring them back to a useable offset. I'm running 8x17 ET35 wheels on mine and have slight rubbing on the rears but with a little trimming they'll be ok.
Wrong way round mate. If you put 10mm spacers on a et25 it would bring them out to et15 not et35! So they would stick out and scuff like a bitch
PS The smaller the offset the further the wheel sits out.