Disconnect a very small connector on each side. (These are for the sounder).

On reassembly, ensure tht the black and white twister wires are fed behind the bracket as shown in the photo.

Remove a long screw on each side.

Remove a short screw on each side. (Ensure that it is indeed the short screw that you use here on reassembly.)

The two circuit boards at right angles should now lift off.

The two circuit boards at right angles are joined by a heat pipe. Take care not to bend this as you may cause irreparable damage.

There is also a sounder on each side which must be prised off and refitted to the new central frame. Again, take care to correctly route the cable.