Note that while 1-16chrd.dat will kind of solve the problem, it will still look a little strange, since there will then be a flat (horizontal) surface connecting the bottom true cone and the top pseudo-cone. To be honest, I'm not entirely sure why the top pseudo-cone isn't modeled using a cone primitive. I'm guessing it's due to the bumps. However, they're not really on a flat surface (they protrude over the edges of the triangles they are mostly on). So I don't think using a cone there would be worse.
Note: I'm not a parts author, and I am NOT intending any of this to be a criticism of the original author.
Note: I'm not a parts author, and I am NOT intending any of this to be a criticism of the original author.