Our PS3 suffered an apparent YLOD attack after about five years. Figuring it was a goner anyway, decided to take a flyer on the iFixit repair kit after watching Fixit videos and guides--and it worked! :) Guide was extremely clear--even down to the number, size/type, and location of fasteners. Took about four hours, but not on all repair, mainly just because we were curious about what was inside and how it was put together. Very rewarding!
Another advantage over just buying a new one was that it allowed us the opportunity to back up saved-game data, as hadn't been done recently at the time the YLOD struck.
One suggestion: The video is good for an overview, but as the video says, when you're actually working, follow the GUIDE and not the video.