Probably the most difficult task in removing a centerboard from the keel slot of a late model O'Day keel/centerboard sloop is getting access to the bottom of the keel because that's how it was installed at the factory. So consequently you need to get the boat to where you can get under the keel and work on it. This alone can be a dangerous undertaking depending on how you intend accomplish it. I reiterate. It can be dangerous and I warn everyone to do so at their own risk.