G'day!
I don't think you'll find a published figure for brake fluid capacity, but I'd say 2 litres will be plenty. Usually I try to empty the reservoir of as much old fluid as possible and then brim it with fresh fluid before commencing, the clutch quite often gets neglected but in my experience tends to be where the most discoloured and dirty fluid comes out of (maybe because it usually gets neglected at brake fluid change time!). I don't think it really matters which corner you start from but I usually bleed the most fluid from whichever point I've started at, the aim being to fully purge the reservoir of all of the old fluid, which then just leaves a relatively small amount of old fluid remaining in the pipes etc to bleed through from the other points. I'd aim to bleed at least half a litre from the first point and then at least 200ml from all the others, maybe a bit more from the clutch. Keep the reservoir topped up at all times- don't let it empty out!
My 2 penneths worth!