You can get a complete E-47 manual from Central Parts Warehouse for $ 5.00 which will show you the tear down and assembly of the pump. The quick answer for the E-47 drain is that it is the 3/4 inch bolt located immediately below the base of the "top can" (where the lift cylinder comes out.)
The fill is located at the top of the can and has a small 7/16" vent bolt located on top of a larger 5/8" bolt. Pull off the vent and you can fill directly thru there.
REMEMBER!!!!! THE LIFT CYLINDER MUST BE COMPLETELY PUSHED DOWN TO THE BOTTOM BEFORE FILLING WITH OIL!!!!!
He has a leaky pivot and the part is on order... (small town and popular part)... on his angle rams coming in to it off the hydro line.... If I keep the resevoir filled for a while will that supply enough fluid to keep his plow going.. it is weak leak ... he maybe looses couple fluid ounces an event....