Pull down the ceiling light and gently tug on the wires and the transformer should pop out of the hole... They often look like this...
http://www.thelightingsuperstore.co.uk/product.asp?productid=13632
Turn off the mains power,disconnect the old and reconnect the new - you may need a screwdriver.
It pays to get the input and output wires right or else the new transformer will fail as it tries to make 4600v
You might like to test it before you pop it back into the ceiling void.
Peccavi, January 2009
