Before doing this I thought, will have to put my phone on the boat to charge, kind of fun. After I thought, I will really need to get another cord to be able to connect the phone to the computer and get data/pictures off.
Wired up the red and black wires from the cord to wires that I had previously put through the PVC elbow into the main container. Wired the red and black from the other end of the cord to the other ends of these. Plugged it into the 12 V USB charger.