Q - Apple 65W ****table power supply

I have a Apple 24V/65W ****table power supply which the 24v lead has a 
frayed coax and needs to be cut and re soldered internally. Model A1021 
  - (Made in India)

Obviously its a push together fit and not designed to be opened but 
there must be someway of opening the case to make repairs.

How does one go about opening the unit without damaging the case.

Thanks