How to open cans for re-wire?

How to open cans for re-wire?
I need to re-cable my headphones after my son severed the cable at the junction. I can't find any screws on the headphones and the soft ear cover that would normally pull off seems glued down on this model. Has anyone ever opened these? Do you need to rip off the soft covers or is there a pres fit joint between the black and red plastic shells?

ANSWERS:

Full procedure