GWWirth I have the boards sitting on the channels I have been trying to level the cab by measuring to the body line hand to shim one side of cab 1/2" to get it within 1/8" of each side. I don't think they cared to much how these things fit when they left the factory. The reason I ask is that both sets of runningboards that I have, have holes on the inside edge like they were screwed to the underside of the cab. Thanks Wayne
