So as mentioned in the previous step, there is a connector for a ribbon/flex cable on the charging board.

You need to take out the 3 screws from the PCBs then carefully take them out and disconnect the cable

Now you're left with two connected modules. There is a 4 pin connector that you can just disconnect.

That should pretty much be it for the teardown. Look at the next steps to get a closer and more detailed look at the internals.