According ihon;
if you drained the tranny and changed the filter, the amount would be close to a gallon (4 qts).
If you drained the tranny and the torque converter, the amount would be close to 6 -7 qts.
If you drained te entire system it would be more like 11 qts.
Obviously, for best results, I recommend using swepco 714-20 atf (available from the ihon website)