Remember all the safety that was achieved by removing the safety plug? That starts to go out the window. All of the batteries are in series, so it’s extremely possible to complete the circuit by grabbing two contacts at the same time. On the plus side, it’ll probably be fewer of the modules so it’ll be less deadly, but still not a good time. The practice of only using one hand – touching only one “thing” at a time – is a good practice here. Until the batteries are disconnected from each other, this is dangerous.
This step is pretty straightforward, so it goes quick. Get a socket, take all the nuts off, call it a day.