It could be done, but you'd need at least two, maybe three 111mm backsprings for the CT layer, and they would have to be modified to match the CT driver.
Also the bit holder part would have to be modified as it would be too short for the CT driver to sit on it when closed, and the CT driver would fall into the layer and be hart do open. Maybe 3D printing a new, longer one that could hold more bits.
And you'd need new pins as the existing ones would be way to short for the added layers.
It sounds like an interesting mod I'd love to see done. I don't think it was done before but maybe some other members have more info