1. The board and battery is designed to fit perfectly into the IPS (V2 or V3) or Laminated GBA shells. If you have an original or old style non IPS shell then some shell trimming will be required. If using the original shell, do not force the battery to fit in the Game Boy Advance battery compartment. Trim more plastic away from the shell until you guarantee a good fit. Along with a small hole for the USB-C lead in the battery cover.
2. Risk of fire if you attempt to unsafely charge or use a battery that has been punctured/damaged. Never use a screwdriver or other metal tool to "lever" the battery in or out of the shell.