1999 ford focus heater direction flaps not working?

Heat is only coming out of screen demister hole. I've removed the switch & suspect one of the bowden cables fron the switch to the flaps is broken.Can I remove the other end (white plastic plate screwed on ,situated on left hand side of drivers footwell) and replace it easily or will removing it cause me more problems.Also,can the cable be replaced or do I have to replace temp switch,flap switch etc plus cables.