Success but it took me more like 3 hours, in part because I had a lot of broken glass. Do tape the glass and do wear safety glasses -- I've never done a repair where glass was flying so much. I did not break the Wi-Fi cable but I completely tore the digitizer cable in the lower left edge. Fortunately I had purchased the full assembly (IF116-018-3) that includes a new digitizer cable. Not necessarily a fun repair but who can argue with a $35 repair cost? The metal spudger (IF145-012-1) worked best for prying up the glass panel. Be sure to read the comments in step 30 to prevent damage to the ZIF connector.
When reassembling I used canned air to blow off dust on the LCD before closing it up.
The ZIF connector lock is almost impossible to see in the pictures, and even tough to see when you're looking at it. It is a really thin black bar with a hinge on the long edge. As Mark Smith and Awfki stated, pull up gently on the long edge that is opposite the ribbon cable. When inserting the new ribbon cable be sure to get the cable lined up, then push in straight and evenly.
Go slowly as you lift up the glass and be sure that you are not tearing a ribbon cable. When I lifted the glass the digitizer cable was torn and unusable. Perhaps I had cut it with the pick/spudger but it tore completely off when I lifted the glass. Good thing I had purchased the full front panel assembly with the digitizer (IF116-018-3).
Echo jesseokerlund's comments that you will have glass flying. I made the mistake of doing the repair at my kitchen table and had a lot of cleanup to do. The job would be much easier if there was no broken glass, and the hardest part is where the glass is broken right next to the bezel. I used the metal spudger to work those pieces free, but it takes some time.
On a few occasions I had an unexpected pop as the glass shattered and little shards struck me in the face. I had taped the surface but pieces at the edge still managed to break free. My advice: definitely wear the safety glasses, and definitely tape the entire glass surface.
I found that the adhesive could be separated when the pick or spudger was in at a depth of between 1/4" (6.4 mm) and 3/8" (9.5 mm). You can always go back and work it in deeper if you are having trouble separating.
My plastic opening tool broke in no time flat. Perhaps I was pressing down too hard and not wiggling it enough. But for me I found that the metal spudger was the best tool for the job. I was able to wiggle it while slowly prying up the glass and once it was under the surface of the glass I was able to work it along the edge quite easily. I saw that some people used a razor blade but I would be afraid the blade would break. The metal spudger was just thin enough to do the job well.
The root of the problem being solved is that the WiFi/Bluetooth chip is becoming dislodged, as can happen when a phone is dropped. Forces on the chip during a collision pull the chip away from the board, creating micro-fractures in the solder connections. This can cause the WiFi (and Bluetooth) to work intermittently. To be clear, there are other reasons that your WiFi might stop working, and you should try to Reset Network Settings before attempting this kind of expert repair.
Why would temperature cycling help? Any time you heat or cool something it will expand or contract. This will cause the metal connections to move - the amount of movement may not be enough to be visible to the human eye, but enough to close the gap from a micro-fracture. This is a temporary fix because it has not fixed the fracture. The gap can open up when the phone gets hot again, or if you drop it again. Reflowing the solder connections can fix the root problem, closing up the micro-fractures permanently if done right.