Lay the device down with the top panel lying upside down on the table and the rest of the device laying on its side.

The top panel is connected to the rest of the device by two ribbon cables:

Ribbon cable connecting the top panel to the mainboard.

Ribbon cable connecting the number pad to the top panel.

Using a spudger, carefully flip up the latches on the ZIF connectors on the top panel and gently pull those ribbon cables away.

Now the top panel is free from the rest of the device!