fork oil change

[rockadoo]

I dont have a manual to work on my GS yet but I'm pretty darn knowledgable about working on motorcycles, especially older ones. I want to change the oil in the front end of my GS. I see no drain holes on the lower legs so I assume they must be drained from behind the axle. If this is the case and I remove the wheel is it a simply let it drain process or does it have to be pumped from the lower legs. Also, how much oil does each leg hold?
Thanks in advance

[90GS500rehab]

I believe its 377ml, you cane drain them by disassembling them or taking out the hex bolt threaded up into the lower will also let most of the fluid out.