Not being horrible but if you are struggling with replacing a light fitting that you have taken down , all you had I do was connect the new one the same. Even if you were an apprentice you shouldn't even be asking this question unless you don't have any idea what you are doing with electrics. Get an electrician in and stop trying to do something which you perceive as a simple task. We train for a long time to be able to call ourselves electricians. Rant over