^ You can disassemble the through hull assembly, and add a port. Look at your port side through hull.... It is a two port assembly. You can add a port to the starboard side to match.
I think you just pull like 3 screws, remove the top piece, add the additional port, and reassemble with longer screws. I had my dealer change mine, so don't quote me on that. I believe that is the procedure though.
I usually do all of my own mods, but this spring is crazy busy at work....