Thanks guys. Good info and advice. Turning power on to the supply after hooking up when possible is definitely always best.
As for the switch, I'm thinking of just converting all of the other switches to "down is on" that way they will all be the same, and if I drive to Europe, I'm all set. I was going to just flip the whole trailer over, but then the hot and cold water control valves would be on the wrong sides, and that might end up being even more confusing, plus I'd have to put the key in the door lock upside down and I was just finally figuring that one out... and I would surely have to re adjust my hitch height. Would my air check valves then be left hand threaded? What other challenges might I run into? We need to think this through throughly. If I do this right, maybe after the conversion, I could sell it to a Lufthansa exec.
Please don't take me too seriously, some things in life are just goofy. You guys are great. Enjoy the ride!