before i removed my front plate and got the "bumper plugs" i had the mounting hardware. i don't remember it being so angled, i seem to remember it was flat on when looked at from the side. (though i should note i did not use a euro plate, just standard us plates so i don't have the extra part. just the main bracket attached to the first set of "blocks")
i just grabbed my plate and looked. i think you might need to rotate the the plastic that's closest to the bumper 90º, so that it is angled from the outer sides to the middle of the bumper instead of top to bottom.
blurry pictures attached:
from the side:
from the bottom:
