Once you open the case, the electrical components will be relatively exposed. The battery has enough voltage to shock you. Foreign objects (FOD), dripping sweat, dropped tools, pulled connector mates and cable ends, or flexed wires could have unintended consequences including malfunction of safety features.

Lay the halves of the case open side by side so that the wiring for the anti-spin-out switch is slack

Disconnect the battery. Cover the battery connector, for example with tape or a small plastic bag.

Cover the battery and controller with a shop rag or towel.