I changed my light to uk spec ones and the bulbs in the main beam were different, there is only two types and they are quite rare apart from in either an FTO or a Ford puma etc, not sure but take one with you, all it is is one is smaller than the other (internal bit that seals it).
Stereo is easy, just take the panel where the gearstick or auto shift is off, then undo five screws from the top section of your instrument panel, then remove the speedo surround thing (just pulls off gently), then prize the bit with all the switches i.e. air con heater conrols etc out carefully, and remove all nesercery wiring connected to the back of it, and hey presto no more car!! joke, then your stereo has four screws holding it in place with the antenna relay and the abs relay on top of it.
Hope this helps if not there is loads of info scattered around.