How do I go about saving a block programmatically? I though it would be the same way as saving a page but I get: Argument type 'EPiServer.Core.BlockData' is not assinable to parameter type 'EPiServer.Core.IContent'

My code looks like this:

            var widget =
                EPiServer.ServiceLocation.ServiceLocator.Current.GetInstance()
                    .Get(contentAreaItem.ContentLink) as MyBaseBlock;
            var clone = widget.CreateWritableClone();
            clone.MyProperty = "SomeValue";
            contentRepository.Save(clone, SaveAction.Publish, AccessLevel.Administer);