This is what I did to fix the problem:
Put some black paint around the screwholes on the harddisk.
Push the harddisk on the cradle (do not push the top of the harddisk).
Since the paint was still wet the harddisk will leave a print on the cradle where the screwholes are supposed to be.
Take a piece of wood that fits under the cradle so it will not stand on its own legs.
Take a hammer and nail and make a small dent in the center of the marked spots on the cradle. (if the cradle would be standing on it's own legs it would bend during this action)
Take a drill (4mm IIRC) and drill the screwholes using the dents for centering.
Get rid off all excess metal around the holes.
You are done. The harddisk should fit now.
