Remove your old drivers first before installing the card.
Then install the card and use only one monitor to install the latest drivers from AMD (and test out the card a little). Using one monitor isn't necessary but I recommend it for the first startup of the card and for installing the drivers the first time.
After the drivers are installed and you can see the card is functioning properly, then shut down and hook up all your monitors using the configuration in my post above.
Boot-up. Usually the BIOS startup screen and initial windows loading screen will only appear cloned on two of the monitors.
When you log into windows, open CCC and go to the "AMD Eyefinity Multi-Display" section and follow the instructions for creating an eyefinity group.
Also, if you have an HDTV and want to hook it up (for movies or whatever), you can still use it independent of your eyefinity group as a 4th monitor (it ends up being a separate desktop). You can even have something displayed on it while gaming on your eyefinity group.
For that arrangement I would suggest hooking the TV to the HDMI port and buying a separate miniDP -> DVI for running the third monitor (instead of using the HDMI -> DVI adapter). This will allow audio to be passed to the TV and will still allow you to have eyefinity.