Yesterday i bought a brand new 2Tb HDD Seagate ST2000DM001 to try to upgrade my 2 year old SAMSUNG 1TB Disk inside my Wireless Space.
1 - just put your new HDD inside the BOX without partitions
2 - do a factory reset to the Wireless Space (push reset button for about 20s, when the red light is on release the button and the light start blinking then push and release the button again)
the system reboot and after a minute a light cycle red,blue,green start for about 5 minutes wait until finish
3 - Enjoy the upgrade (default IP 192.168.1.1)
It seem unbelievable but works,
Then upgrade your BOX to actual firmware is you wish for me the system wake up with 1.07 version
The disk is automatically partition in GPT so i think that the box will support 3TB HDD,