usually you need to remove the back pannel and the right hand side pannel to get access to the heating elements and the wires. The panel is secured onto the rear panel with around ten philips screws which must be undone and the cover plate removed.
Be careful with the elements as they are usually on card.
The right side panel removes by undoing the screws on the back and bottom.
Hope this helps but not sure of the model you have
Max
November 2006