Remove three screws from the back.
Now you can push the top lid a bit forward and lift it up and away.

Lift the keyborad cower up.
Remove a screw and a plastic cap on each side.
Now you can roll the cover up and pull it out where the plastic caps where.

Here the plastic caps are dismounted.

Be carefull not to scratch the wood pieces.

Now you have access to the floppy drive.

You will need a screwdriver with an angle - there are four screws underneath the floppy drive that needs to be removed.
See the entry "Changing the drives" for the electric stuff.