Great guide ... managed to upgrade my 320GB to a 2TB drive with no real fuss. NOTES ... you should get a SATA external dock and do the OSX install and TimeMachine recovery so your HDD is ready to go. You should boot test as well before the change out procedure. One recommendation .... when you reassemble the front glass to the LCD its a good idea to let an air purifier run for a few hours in the room first. Wiping the LCD builds a small static charge and dust immediately sticks to the glass or LCD. The air filter trick was magic.
This was near impossible to remove as there is no room to grip the connector and no easy way to wedge something in there to help remove it. I felt like giving up but the hard drive removal and swap was so easy you just need to get someone to hold the screen for 10 minutes. Don't try removing the cable ... you most likely will get frustrated unnecessarily.
The Torx set I bought from ifixIt is well worth the money. My screw heads in this step were T9 not T8. THe T8 bit was too sloppy in the screwhead and there was a risk of rounding the slots. Having the option to go a size-up was perfect.