The factory cable is a 16'. The smallest cable Defenders carried was 17' so that is what I used. I had to put a small dip in the cable under the gunnel were the cable hangs from some PVC that is fiberglassed under the gunnel to take up a bit of the extra length.
Here is a shot under the gunnel.
The motor hanging from the cherry picker.
From the other side.
I was happy to see no water intrusion.