When the tubes are removed and turned upside down, the oil draining out is much darker than what can be siphoned off from the top while the tubes are in place.
Loosen the top caps. Remove the fender and wheel. Loosen the triple tree clamps then draw the tube out of the bottom of the ttttree. Then remove the cap while watching out for the spring that is under pressure. Remove the spring and spacer then turn it upside down. Pump the beast some time. DANG sometimes you will find that after pumping the fork it won't extend fully anymore. Some folks use a wooden dowel (broom Handle) to un-stick it. Huh? Instead of that nastiness simple slide the axle into the fork and using a rubber mallet give the axle a light tap. Viola! Unstuck with no nasty wood bits in the tube.
Hang the suckers upside down for 30 minutes. Heck you can even drain them, pump them to get most of it out then add some more as a flush. Then hang em upside down....