Simon,

I used closed cell (low moisture absorbsion) foam formed into wedges, wrapped them in fibreglass then used epoxy to glue the inserts to the fore and aft faces of the centreboard cases. Make sure that you allow for cured fibreglass thickness so that you can insert the wedges in the case and get the right depth.

Remember that the bottom rear edge of the case is probably the limiting constraint. Measure the existing draft angle of the rear case. Rule 5.11 states "The leading and trailing edges of the centreboard slots shall be parallel and within 10 degrees of the perpendicular from a straight line along the tops of the main and rear beams."

Maybe you already have these draft angles in which case you would only need to pack out the front as required and use thin wedges at the rear to ensure that the boards are kept in line with the hulls.

Check that your existing boards are centred in each hull. If they are correct then mark the front and rear edges on the hulls and deck. This will provide a reference for the new boards. It is critcal that the boards align correctly with the hulls.

If you are unsure about how much packing is required, make some temporary packing and see how it works.

I don't know much about the use of lining with carpet so I will leave that to others.

Regards,

Peter