While you’re here, disconnect that SD reader cable and don’t forget to plug it back in on your way back through: it’s not mentioned elsewhere in this guide.

You can. Fold the computer all the way over and go from there. The only advantage to opening the bottom would be to disconnect the battery: a highly recommended procedure.

I successfully completed this repair. Went from 500GB Seagate to 1TB WD Blue.

Problems I had are limited to the thermal connector would not fit the hard drive I bought. I'm pretty sure the pins on my new drive are for an 8-pin thermal instead of a 4-pin, and I just left it unplugged. The fans spin at full speed now, but that's hardly a deal-breaker.

I got an extra screw hiding under the rubber gasket holding the end of the heatsink to the chassis. Ended up bending the heatsink a little cause I wasn't looking for it.