Sorry to necro-bump, but I'm hoping this info will help anyone coming across this thread in the future.
It's also 6cm from the fender crease to the bottom of the emblem (
as seen here), and IMHO you should follow the line of the crease (i.e. level the emblem with the slope of that fender crease, not the ground), or it will look (slightly) crooked whenever the car + observer are on anything other than perfectly flat ground. Ask me how i know.
In other words DO NOT DO what is in the attached photo (where the emblem is set with a level / plumb bob). The top of that piece of paper *should* have been aligned with the crease. It's a small difference in angle over such a small distance, but once you see it it's hard to unsee. I ended up having to remove + re-do these emblems after they annoyed me enough.