I am installing new banisters and am currently at the stage of fitting the handrail. I have bought the handrail fasterners from wickes but when i took the old handrail off i noticed a morticed cut behind the handrail. It was held in with nails and I have no idea what the rectangular mortice is for. However this means I cant use the fixings that I bought from wickes. Is there any other way to attatch the handrail so it remains strong and I get a good fit?