That helps a lot. Thanks.
However, looking at the images I would not recommend switching the default bottom intake fan and mounting it above the HDD cage as the PDF file suggests. The grill above the HDD cage where the fan is to go is mostly blocked by the superstructure of the HDD racks below. Not only that but some of the air will be drawn in from inside the case itself via the grill to which the VGA airduct attaches. Actually, if you look inside the actual case you will realize that just about all of the air will just be re-circulated within the case and little or no fresh air will be drawn in from the outside. I don't know why they would suggest switching the bottom intake fan and placing it above the HDD cage.
Mounting a separate HDD fan, however, is a different thing. I see, however, that it would take up at least two of the 5 .25â€ bays leaving you with only two or possible three 5.25â€ bays left. It's too bad that the only way to mount the fan is inside of the very tall plastic clip-on housing which takes up a whole bay extra.
Oh well, thanks again.