I store my tank in the starboard lazarette when I am not on the boat as well but do agree that it is not the best idea. when we are aboard, it stays in the cockpit.
All of my I ran 8 gauge wire from my battery in the port rear quarter to my switch panel that I mounted on the stern end of the galley where you can reach (& see) it from the cock pit. The stereo, bilge switch, and 12 volt outlet are all mounted there as well. Again, so you can see and reach it from the cockpit. I do want to add another 12 v outlet on the cockpit area to plug in my phone or handheld gps and such. I ran the ground to a single stainless bolt that is long enough to stack all of my other grounds on then tightened a nut down on it to keep everything secure. I will have make another vid to show it all. I also replaced the nav lights with LEDs to prolong my battery.