The following info is not given until step 21 in the instructions, and probably too late at that.
DO NOT disconnect or reconnect any of the cables in this device until the battery itself has been disconnected!
Don’t skip that step, intending to do it at the end, as you may damage the phone.
It is physically impossible to use the plastic card as shown, unless the battery has already been loosened by some other method. Is the photo provided to justify the use of an extra tool?
The important warning about making sure that the battery is disconnected may be more beneficial at the BEGINNING of these instructions.
Pulling up on the “nub” is a futile waste of time.
Use two spudgers.
One placed in the original breech position to be used as a wedge.
The other to get worked around the unit.
These spudgers are going to get destroyed in the process and will not likely be great for another repair.
What is unfortunately unclear is just how to 1. apply sufficient force and keeping the phone secure with only one hand, 2. whether this is best done on a table to use its opposing surface to secure the phone.
The suction cup is a worthless tool because flexes too much to provide a good hold. Mine slipped and popped away three times. -The last time causing a crack in the screen.