I decided to modify the design a bit and make a hotrod for my kiddo with red interior and flames. The material is all purchased from the local hardware store. The base is a 1" x16" 36" pine. The sides are 1"x12"x36 pine. The curved rear is made of thin 1/4" ply. I soaked it in water for about 30 minutes then bent it over the frame, nailing it every 3 inches or so. Next time i'll probably just use some sheet metal. I had the conduit laying around and purchased the wheels and the little switches. Then primed and painted it with gloss black and apple red. I traced the flames on some paper and cutout stencils so both sides match. To bend the trailer arm, since i didn't have a conduit bender, was just to put one foot on it about 16 " from one end and pull up on it until a got the correct angle. The hitch is just a piece of steel strapping i bent into a "U" shape and a locking pin from the hardware store.