You shouldn't need to get any mounts as all non-M versions of E70 have the same PCD and hub diameter.

However since you originally have 20's (20x11's at the rear), its safe to assume you have the extended flared wheel arches. If this is the case, moving to 19's will give your E70 a toe in look (narrower wheels under a wider wheel arch).

One way to address this is to fit wheel spacers to the rears, to push the 19's wheels back out. That is if you're worried about aesthetics. If you're not. all should be fine then.

__________________
H@mmer
"Don't take life so seriously, it's not permanent"