I've just bought a new extractor hood and need to change the flue too as the old one is a different size and doesn't fit properly on the new hood. This is a nuisance as the old flue already has a hole cut in the side for a PVC duct to vent the gasses through an exterior wall about 2 metres away. Unfortunately the flue that came with the hood doesn't have a hole in the side and the manufacturers (Candy) say they don't do any other versions with a hole in. That means I have to cut one myself, but it's made of stainless steel and will need a machine tool apparently. Any advice here, such as how to cut a hole in the flue without ruining it or where to get another flue with a hole in the side (that fits)?