On my 2004 Galaxy there is no leavering to do. When the two 10mm bolts that hold the grab handle to the metal have been removed the whole door card can be removed with a vertical motion. Some of the wires are not very long so go carefully. The door handles are connected by a flexible cable which can be unclipped. Jonesmabel
If you loose the central locking, the interior lights, the direction indicators and perhaps other stuff, look at the 3A fuse in the fuse box close to the battery. This applies at least to the 1.9Tdi 2003 Galaxy.