Transmission cooler replacement
 

We have a 2010 e60 with N52k.

I'm trying to remove the transmission cooler from the radiator. It looks like there is a black, plastic release lever, but when I move it nothing happens.

Does the lever need to move from 9 o'clock to 6 o'clock or from 9 o'clock to 3 o'clock to disconnect the transmission cooler from the radiator port?

Is there a step before or afterwards to remove the cooler?

Here's a technical service document issued by BMW to dealership service departments for techs. Take a look. https://www.newtis.info/tisv2/a/en/