Whoa, a hammer? Easy there fella! Open your trunk, and there are two square caps that pop out and hide screws that hold in the lights. Then, using a screwdriver wrapped in tape, or a wooden/plastic pry, pop out the corner lights. They are shaped like a "D" and the straight side has a metal clip that allows them to pop out. You will find another screw and the assembly comes loose. Twist the lights out and replace.
Just remember, this is a Toyota, most solutions are simple and gentle.