I own one of these too.
For changing the fluid in the reservoir, I just stick the end of the plastic vacume pump tube in the reservior and pump the handle to remove the old fliud. to really get all the old fluid out this way you must do this more than once and the intervals are preceded by driving around or starting the engine and moving the wheels full sweeps left and right.
This procedure is NOT called bleednig the power steering system which involves forcing fluid through the hydrolics system to remove oil fluid, air bubles and other contaminants. Consequently, if your system has air bubles, or contaminants changing the powere steering fluid in the reserviour will not help.