How to replace FCKeditorAPI GetInstance

we are updating to ckeditor 3_6.1 from FCKeditor. In our code we create the FCKeditor as

function createEditor() {
    fck = new FCKeditor("myFCKeditor");
    fck.BasePath = "/ACES/CKEditor/";
    fck.ToolbarSet = "BOE";
    fck.Height = "100%";
    fck.Width = "100%";
}

we then create an instance of it as such

oEditor = FCKeditorAPI.GetInstance("myFCKeditor") ;

Is there a replacement for the GetInstance in CKeditor?
thanks.