Also-
I can't remember how the Sol Cats keep the boards down, but what I remember from sailing a Sol Cat is the stock boards are HEAVY- ie they sink. Your new boards will likely float, ie when you put them down they will tend to float up. Use a system like the Nacras- originally they used a bunji from the top front of the board going forward to the hull then switched to a "side loader"- a rubber covered bit of PVC as long the board with a bunji loop running through it and connected to hooks/loops so the tube has to be pulled slightly to the side to put the board in so the loop puts a sideways pressure on the board which will keep it up and down.
Just a thought-

Kirt