Wow, I get to correct olegil :-D
It *should* be a snap
1. Front Bezel Off (remove with a large flat screwdriver)
2. HDD slides out on plastic tray. (HDD may need 4 screws unscrewing)
3. Unplug IDE/Power and plug in new hdd.
The hardest thing is normally getting the power plug out as it's wedged in so tight!