Hi Scott,
When I did my transmission change the level showed about an inch above the full mark. I had some clear plastic pipe and fed it down the dipstick hole, I then put my finger over the top hole of the pipe pulled it out a few times and emptied it. In all fairness when the level had fallen below the max line to bring it into spec I had taken less than 100ml out. Didn't seem much of an overfill to me for a 9 litre capacity, but MB say not to overfill so I just did it, may have been a different approach if I knew it was going to be leaking out.
Norman