There seems to be a belief that your stainless trolling wires must be isolated (insulated) from your boat. Here is a video I made up a while back showing voltage that a fish sees (using 2 meters). I show a caribiner to connect up with. That is a quick and easy method. The picture below is probably a tidier system with a metal tube that the wire goes through and makes contact or a stainless spring that is free floating between drum and block with a connecting wire to it (Cannon used a spring). Anything you use will have to be large enough and strong enough so as not to get fed into your drum or block and making a mess. I will follow up soon with another video explaining a boat's bonding system for those who are interested.

Vide: https://www.youtube.com/watch?v=elDMKAvl0Jg