Changing Power steering fluid on 2006 sprinter?

I like working on my own vehicles and changing the fluid seems like a pretty simple and straightforward procedure that i've done on several cars previously.
is there any mercedes specific quirks i should know about?
also, how much of the Mobil ATF-D will i need?

also, if anyone can post up a section from the FSM (section 19, steering IIRC) about this, it would be greatly appreciated.

thanks ahead

Look here...

https://sprinter-source.com/forums/showthread.php?t=2748

...according to the service manual, you don't have to replace the fluid. Just fill it.