If you make the LBM the same as the predator ferrule it will crack as it is harder material and cannot take the punishment. If you put another tenon and then make the LBM thicker it will stand up to the abuse but the shaft will then hit like a Dominator or any other splined shaft that is not hollow in the nose as you have now added weight.
As it has been stated if you change ferrules you void warrenty.