1 - 2 horas
I had the Yellow Light of Death and I did not want to send my PS3 in for repairs to places that I did not trust.
The repair process did not go as smooth as I would have hoped. For one my PS3 was an old 40gb that was not backwards compatible. This made it hard because the guide was completely different from the inside of my PS3 so I had to go looking for guides elsewhere. Besides trying to find a better guide, everything went very smoothly as a took my time to organize everything for a safe reassembly.
For people with older models, the PS3 probably looks a bit different and one might need to find a better guide. Also make sure everything is nice and tight when putting it back together. I mistakenly didn't put the Blue-ray ribbons in tight enough so I had to reopen in order for my PS3 to recognize games again.