Hi Ralph,
I haven't touched my wipers for decades but, as I remember when I did, the motor and transmission would separate from the cable and housing. This allows you to remove them and work on them out of the car. To remove the cable from its housing, I believe you must remove the wipers so the gears can revolve completely as you pull the cable out (a task necessary if the cable lubricant has solidified or a particular wiper gear of cable section has been damaged.
Good luck,
Ray (64BJ8P1)