Spigot ferrules? They still have an insert so they are thicker than the rest of the blank (flat spot). Rods with tip over butt ferrules are built in pieces on different mandrels. As far as I know the mandrels are the same. If there is a rod you like you could contact the manufacturer about making it one piece. They would need to design a cut sheet for the carbon fiber so it could be rolled on one mandrel. Chances are they won't do it for one blank but if you get enough people together they might.