You'll remove the stock cap completely, and thread the pop-up or put Monza cap parts in. Nothing else.My question to Todd, however: The standard V7III gas cap has a cage in the tank opening that provides two things: a necked hole for the fuel filler nozzle and an air hole. When filling the tank, I top up until the fuel comes up to the air hole, which leaves the correct, minimum amount of air space at the top of the tank; it prevents over-filling the tank. So my question has to do with whether this cage would stay in place with either the Monza or CNC popup caps.