Easy peasy.Can't help with a cable but well done for getting that case open!
Easy peasy.
Circlip pliers. The ones that spread the Circlip wider when you squeeze. Wedge into where the flap for the cable winder and squeeze. Pop.
Awesome - thanks for the tip!
Why dont you just shorten the cable a bit past the break and resolder?
a new cable will, this could be done in the interim if you needed to.