Tranny Oil G005000 Amount Needed

[Brice Warnick]

How many litres of G005000 do I need to drain and refill the tranny? I
am guessing 2 litres.
Nowhere in the Bentley does it say how much.
Now, when I find out how much I need the next question is how to do it.
I have heard that you should take off the fill hex bolt first because if
you take off the drain hex bolt and find that you cant get the fill bolt
off you got a tranny with no oil. 
Are both hex bolts 17mm?
I have also heard that not all of the old oil will drain out and that
you will have half a litre left over and that you should drive the car
around the block and then top it off with the remaining half litre. Is
this correct?
What is the best type of funnel or hose to get the new oil in with?