Just did the first oil change after the rebuild. About 15-20 minutes runtime, oil came out looking nice and clean, but it had to be done.
Anyway, as I was changing it, I first drained the tank, out of which I got roughly 1.5 litres, and then I drained the sump, which had 1-2 litres. These are estimates, so there could well be a good bit more that came from the tank, but I'm just wondering how much oil is normally sitting in the sump in this "dry" sump system.