Sensor is on the bottom of the overflow. Lift the overflow unit/ tank up, follow the wire and unplug it. Thats all you need to do to get to the hose to remove it.

Cover the alternator with plastic and swap the hose. Most people use a generic flex hose now.

It would be a good opportunity to change the t stat and do a coolant flush also with that lower hose off. I like to drain all the old stuff out and put in water and some coolant flush. Then I undo the lower hose at the radiator and flush it out through the top cap.