Below you see how it pops out relative to the main step.
Finally, here are the steps about to get a layer of glass before being glued together. My thought is too reduce the amount of damage done by the base of the mast. Wishful thinking maybe?
As mentioned in Part 1, the forward step requires some method for keeping the buoyancy tank airtight while still allowing the mast to pierce its space. Enter the mast box. The pics are self explanatory (I hope) but I will add that one step not completed is using fillets in the interior corners of the box, under the top flange, and where it meets the step when installed in position.