Navi Plus retrofitting

Hello.

When retrofitting a Navi Plus, it is always pointed out that the instrument cluster needs to be renewed if you want to see the direction indicators in the FIS. Xenon Mann says this is not necessary, the level 3 of the instrument must be unlocked. I have not yet been able to find any information on this. Is the statement correct and where do I find out exactly what I have to do? Can anyone help?

Greetings from Hamburg

Andreas