Trying to end the discussion in the Forum. Mitkos sea card is correct! Alexander Trabas helped us to identify the Rear light by a street view picture!
What is realy confusing, the Front light at sea front (C7430) has a triangle with tip down and the Rear Light has no triangle! Now we looking for the next visitor to make a great picture of the Rear light! ;)
Great that we've sort this out!