[Hermi]

You can use It. But you need to mount it under the roof. The antenna will be directly mounted on top of the atm. Or you build a custom adapter.

Can't I just use a fakra extend cable from Antenne to atm instead?

It'll be fitted into an E60

You must build custom harness with custom plugs, but never see something like that. There are no fakra connectors for antennas on white roof ATM.