http://www.hdforums.com/m_1835225/tm.htm
Guess with all the $$$$ that you saved, you could have invested in the Service manual..
The Primary and Trans share the same fluid.... it is easiest to fill through the Primary chain inspection window, as you need to view the correct level at the derby cover.... capacity is 1 qt....
Another advantage to having the Service manual, is it will give you the correct specs, ie. Proper primary chain deflection, correct Clutch adjustment procedure, steering stem adjustment, and all of the required torque specs.....
BTW, take a moment and post an intro in the new members section... Welcome Aboard...