Fork oil question

I changed my fork oil Sunday and all went pretty well. I say pretty well, because I have a question about oil level. It wasn't where I expected it to be. The Ducati spec called for a 108MM air gap. I am very careful to measure things before I go past the point of no return, especially if it is the first time I have done a particular task. This was the first time I changed the oil in these forks, so I documented everything as I was taking it apart. I measured the air gap before dumping the oil out of the fork. It was only 55MM. The only thing that makes sense to me is that I didn't bother to remove springs or anything. I just let the fork body slide down on the inner tube. I assume that if I had removed the spring, I would have had closer to what I was expecting. So, this is my question. Does the air gap that Ducati specs assume you have springs removed, or did I just put WAY too much oil in my forks??? In any case, I replaced exactly what I took out (excluding the oil weight) and I used just shy of 470ml in each fork. Ducati also specified 570ml, but I am sure I didn’t get all the old oil out. Everything was fine before, and everything’s seems fine now, just wondering...

Oh, the oil level was different by 10MM between the two fork legs. The other fork leg measured 65MM for the air gap before dumping the oil. I set them both at 55MM. For a measurement that seems to be pretty critical, I would have expected closer tolerances between the legs!

Oh yeah, the bike is a 2001 900SSie with the fully adjustible Showa forks...