Have a look through a few build threads on here pretty sure Dom is using 20mm spacers all round and he has plenty of pictures on his thread along with other peoples builds.ED38 are mad for spacers and stretch plenty of info on there.My own car has 18x8j ET35 10mm spacers on the rear and 5mm up front no real poke more flush on the rears which suits my own car but if your after more poke and stretch maybe 20mm spacers would be better.