To the OP, Wisdom is recognizing schit before you step in it. It pays to know when you're in over your head and back away from a job before you cause secondary damage. If you find dis-engaging the cables at all complicated, or are tempted to pry, bend or use force, you should probably quit while you're ahead.
Cable removal from the levers or shifters requires finesse, not force. I'd like to help you, and usually don't like to send folks off to the shop for things they can learn for themselves, but at the same time don't want to lead someone into a pile of crap.
If you're struggling, bring the bike to the shop, let them do it for you, and ask that the mechanic let you watch, (or that he teach you) so you'll be able to next time.
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