Before you start, read Generic Safety and Compliance Notices and print the following instructions.
Disable the built-in battery. See Disable Fast Startup and the built-in battery.
Turn off the computer and disconnect the computer from ac power and all connected cables. Then, close the computer display.
Remove the nano-SIM-card tray if your computer comes with one. See Connect to a cellular network (for selected models).
Remove the base cover assembly. See Base cover assembly (T14 Gen 2 and P14s Gen 2) or Base cover assembly (T15 Gen 2 and P15s Gen 2).