If you look at the smaller bottom PCB you will notice 2 wires on both sides of it. Slightly above that there should be some hot glue holding these wires to the plastic housing. You cannot see it in the picture but its estimated location is highlighted in red. Remove this and any hot glue that's holding the main power cable in place.
When the glue is removed gently lift the lower plastic piece and the bottom PCB at the same time. It will come out as one whole piece.
Place the electronics off to the side.