All you have to do is clip the line to something, it don’t have to be you. Clip it to the fishfinder.
Clipping it to a fishing net is not going to stop ther boat if the operator falls or goes unconscious as it will not kill the engine.
The law requires that boat operators of a motor boat 26 feet or less in length be physically connected to a boat’s emergency shutoff switch. Older boats that don’t have the system installed by the manufacturer don’t need them. But boats purchased from here on will so the thought of jerry rigging one will be out of the question in time as they will just write you.
If the warden finds your clip to the net, you will be issued a warning and later a $200 ticket.
rwood