|You are quite right Alex, |
I recommend that you use a filler to prevent the keel from falling back into the box when you are knocked down. It is a very positive and watertight method as against the bolt system. It means you will have to change the top end rear cover of your centre board box.
In the other boats where they use the bolt through the box system you will find that no one bothers to fit the bolt once the keel is lowered even though it is required by the racing rules If made using a flap the filler can also improve performance of the boat by reducing turbulance in the rear area of the box. In Victoria you will receive a very heavy handicap penalty when CBH racing your RL 24 if you fit a flap!!
I will photograph my filler and the quick release top cover system fitted to my boat and if possible put them in this forum site.