the trick to the self adjusting cable is you compress it using the white clip thats flopping loose on the cable, you shouldnt need to jack it up the clutch arm.
though if the clip above is missing you would have to jack up the arm or chop the cable. compressing the cable like this resets it so in theory it should work again with a new clutch, but they often just break so never work right, new one is required in that case. I would always put a new cable on as a matter of course anyway