You will have to remove the panel on the rear hatch. After that, you will need to drill all the way through the back of the existing threaded plate holes. Once you have that, screw the led's in, and use some tap-in connectors to splice your led's into the existing license plate lamp wiring.
My brother-in-law installed some blue led's in the license light housing so it points down and makes a blue line on the egde of his license. It looks really cool on his new blue Mazda 6.Yours look like they screw into the license plate holes. Just fine some power source to tap into, like the license lights or brake lights would be cool, too.
18" Enkei's & Kumho Ecsta's-------UNICHIP Eibach Sport springs----------Morroso oil pan Injen CAI & Oil cap----------Stage 2 FI cams Custom Exhaust-----------TRD Supercharger AEM alt. pulley -------JSP Carbon Fiber hood 380cc injectors----DC Sports ceramic header