How can you instal lighting without the knowledge of where you are alowed to run wires,? allowed to dril holes in joists? or cut notches?, ultimately these considerations tell your client where they are allowed to have their lights !!!- yes we can put a light anywhere, sometimes its at great cost because of the above considerations. And another thing, No sparkey will certificate a new circuit unless he saw the wiring run going in ! Re read my message mate ! give you a clue to real life lighting, its cheaper to put a pad saw through a ceiling and re board it rather than have a chipbard sheet bedroom floor up and back down. If you wana replace a light fitting with another, then its just a replacement unit- I think thats all you had better stick to at the moment. Yep, any sparky will come along and connect it up for you.