marso - I'm sure it will be a challenge!! But I'm going to have a go anyway
The rubber tipped dowling sounds like a good idea
jimmythelock but since there is a space in the spacing (great English eh? You would never guess it was my first language!) at 12 O'clock (as shown in the other link - great link btw) I think you could stick some windscreen wiper metal to the face of the lock using some silicon and wait for it to go off to apply constant tension. I suggest silicon because it will hold quite well yet leave no residue when you have finished and clean it up.
Worth a shot but I guess I'll have to get a practise lock to try it on - can't see anybody here at work being to happy with me siliconing things up to 'test'
So go slightly off topic, should you pick it and turn it eversoslightly, I imagine the pins will remain set allowing you to cast a 'key' somehow. Anyone have any ideas on good casting stuff?
Thanks for everyone's input on this.