(When re-installing) Before screwing down the logic board, go around the edge and make sure no cables are caught underneath, remember there are 11 of them, 12 if the battery is present at this point.
I used pointed tip of one side of the tweezers from the ifixit Home Tech Toolkit. I found this thinner pointed tip better than a spudger for hitting that notch in the socket underneath the connectors. Since this is a metal tool, I pried very gently and I was working on a MacBook with the battery taken out entirely (early on as suggested in the video) and was also using an Anti-Static wrist strap. I found the spudger broke one of the connectors because it's relatively thick plastic, and put too much pressure under the cables before the tip could reach the plastic block of the connector. The pressure under the cable popped the wire contact right through the top of the plastic block connector. (it was OK this connector broke since I didn't need to reuse it--my replacement keyboard/upper case came with its own cables.)
Because the tips of the tweezers are angled, I felt I had better control of the torque I was applying than if I used a jeweler's flathead screwdriver.