First, you will have to remove the old body from the base of the RC car. Don't get frustrated, at first it's hard. But it's not. In the RC car model I used, there will be a plastic stick left on top of the base, were you will be able to attach the first Lego. Go to http://www.newbright.com/product/view/id/56. Or go to http://www.newbright.com/product/view/id/96. The second website is for the RC racer. To remove the old silvered colored body piece from the car, place a screwdriver under the piece, then push back words on body piece. It should come out easily.