it is possible to screw them up. i've heard that if you get the wrong bands in the wrong side, the t-20 will work backward and then tear up the drums and bands. just follow the rebuilding article and pay close attention to which side the plungers go on, and which direction the bands run from the anchor to plunger and you you will be fine. http://www.6x6world.com/forums/conte...kid-steer.html