25.3 spec 4130 chassis. This cage fits inside the rocker panels mounted on 4x4" .125" ms plates. The cage requires the floor to be removed and placed in through the bottom of the body. These chassis assemblies come tack welded, and ready for you to weld. The rear section of the chassis is tack welded together but is left off the back of the chassis. The rear section must be installed after the main section of the chassis is installed inside the body. This assembly can be shipped.