5 - 15 minutos
I was running into too many SBBODs (Spinning Beach Balls of Death LoL). When I did a restore to try and fix the problems it took up to days. Like three to restore. I then ran a disk check. Apples internal check showed no problem but I ran Volitans Smart Utility and it showed the HD was failing. So with nothing to loose with a computer that I couldn't use I decided to embark on a task that I've never considered before.
I followed the slide show of the repair after setting aside some time and space to do the repair. I've always said that most anxiety comes from 'mystery'. If you take the mystery out nothing becomes difficult. The slideshow and IFixit did just that. Because I went slowly making sure I got everything correct it took about an hour/hour and half. No hitches. At this time it is restoring from Time Machine with about 2 hours to go.
The only thing I would advise it to review the instructions/slide show a few times before attempting a repair to familiarize yourself with what comes next when you are doing a current task.