How do u update my my wow from 3.0.1 to 3.3.5?

I've been trying to find a way to update my World of Warcraft version from 3.0.1 to 3.3.5, every time i use the updater it tries to download 4.0.1, and when i look to download 3.3.5 its 14 gb? I'm pretty sure that's the full game, if anyone could help me i would be very gratefull