The best way to clean the cable in a power spin is to manually pull the cable out of the unit. I generally do this in an area where I have some room to lay the cable out in front of me.
The cable is attached to the inside of the drum so once you get to the end you will feel some resistance at which point you can stop puling.
Cleaning is really wiping the moisture off of the cable, especially if it is not going to be used for a while.
While we no longer sell the rust inhibitor, rag moistened with some oil will suffice to help prevent rust and corrosion.