I ground down the flanges of my verticle stab rib to get the clearance for the slingshot. This is to prevent crackin in the verticle which was found a few sportsman due to the two piece verticle. I aligned it and drilled the holes. I touched up the bare metal with primer and riveted it in place. To get a good fit on the wings I made a QCell bed to get at smooth fit. It is the same technique used for the rear cage attach brackets.