2 - 4 Stunden
I had an external hard drive that I used to stream movies to the Apple TV, but it was noisy and the external drive didn't recover well from sleep.
The repair process was relatively easy thanks to the guide and the video combination. The only trouble I had was that the last screw for the assembly holding the drive was some new Apple security screw. Luckily, I managed to wedge everything in place with the assembly still screwed down, but it wasn't easy.
The supplied cable and rubber brackets fit and worked perfectly. The included screwdriver set was poor quality, but good enough to do the job.
If you have one of the Apple security screws and you can't remove the drive bracket, to get the rubber grommets in the back into the plastic frame, but a screw bit between the aluminum wall and the plastic frame, then push and twist the grommets in. I was able to do it without breaking the frame.