Help me optomize my system cooling!

Hey there! First build, need help optimizing my cooling.

Here's what I got.

i7 920
Asus P6T Deluxe
2x GTX 275 SLI
http://ncix.com/products/?sku=3742 [...] FMicroStar
Corsair XMS3 TR3X6G1600C9 6GB DDR3 3X2GB DDR3-1600 CL 9-9-9-24
http://ncix.com/products/index.php [...] re=Corsair
TX850W 850W CMPSU-850TX 12V 70A 24PIN ATX Active PFC 140M Fan Power Supply
http://ncix.com/products/?sku=3515 [...] re=Corsair
Thermalright Ultra 120 Extreme 1366RT Heatpipe Cooler LGA1366 120MM Fan FDB 1600RPM 28.0DBA 63.7CFM
x3 120 mm fans
CM HAF 922

Questions:
1.The cpu fan. Should I set it up north-south or east-west? I have it set-up north-south right now, my logic being that it will draw air in through the p6t's northbridge and that the exhaust fan on the top of the case is larger than the one on the side.

2. Side fans (120mm)? Yes or no? One would be a quarter over the heatsink, a quarter over the RAM, and the lower half over nothing. The other would be the right half over empty space, most of the left half over empty space between the two graphics cards, and the remaining portion under the bottom graphics card.

3. Bottom Fan (120mm)? It's right side would be nearly touching the HDD drive bays.

4. Causes for concern? The second video card is right over the PSU exhaust fan: the second fan on the videocard, which draws air in, is almost directly over the PSU exhaust fan with barely any room between them.

5. What do I do with the drivers for the videocards? Nvidia's are quite a bit newer than MSI's, but I'm afraid the second fan on the cards won't run properly with Nvidia's drivers. Also, will that cause me to lose the factory overclock (I suppose I can just jack it back up myself)?

6. I have three HDDs. How should I position them?

7. Will it have decent cooling with suggestions taken into account?

Thanks!

P.S. I'd be testing this myself, but right now I'm sitting with a RAMless computer (RAM got lost in the shuffle, just got shipped); however, I'm hoping you experienced guys have some conventional logic that won't make me go through some tedious testing later on. I'm planning on OCing, but nothing crazy (920 to 3.5 GHZ and have the RAM 1600, even though it's supposed to run at that but doesn't out of the box). Maybe OC the videocards when games get harder to play on this system.