I have to fit a chimney hood which passes through a flyover shelf. Tiling will go all the way up to the shelf. Would you tile first then fit the hood, or fit the hood and tile round it? (It is one of the curved glass variety, which would make for some interesting tile cuts). My thoughts at this stage are to tile first, but wondered what the pros do. Incidentally, what would you do if you had to fit the hood to (an untiled) wall that was out of true - I don't fancy scribing a stainless steel chimney!