You need to remove the back panel first, Remove the heater cover and the undo the two screws securing the heater. You will slao bneed to disconnect the mains connections in the two spade terminal that attach to the block on the back panel (top right (looking from the front). Also you will need to release the rear drain port from the back panel (it may have water in it) by removing the two screws. also there are four screws that hold the fan duct to the back panel - you need to take these out. Remove the threee screws that secure the rear drum bearing mount. You can then remove the back panel. You should aslo be able to lift the drum out of the way. Bottom Left (as you look into the back) there is a white duct. This is held in place with two clips (top and bottom) where it joins the main duct ducting and a small self tapper onto a bracket underneath it. Remove the clips and bracket screw and you should be able to remove it which means you can now slide the new belt onto the motor shaft. And as they say in Haynes the reassembly is the reverse of the disaasembly. Only thing i found id it is easier to mount the drum bearing before refitiing the back panel.
Hope this helps.
Timbo, January 2008