We (my dad and I) bought a 77/78 SS parts bike with no title. We got the tank from it then we measured a few hundred times it felt like. We then cut the hinges and seat lock off the SS parts bike and welded them on the k3 frame. Everything lines up perfect. For the tank the k3 frame needed no modifications, only thing needed was the rubber at the back of the tank where is meets up with the seat. The original rubber piece wouldn't work so we used a SS one.