I just picked up 2 - 6 volt GC batteries at Costco for my TT. Of course my old 12 V battery box will not work now. I have noticed that a single 6V box is $10-20 while a dual 6V box is $70+. Has anyone had a problem using 2 separate boxes for their 6V batteries? It is certainly cheaper that way. It is also easier to remove from the TT one at a time. My batteries and propane tanks are in an enclosed area (vented of course) at the front of the TT. They are not exposed to the rain. Has anyone just used hold down straps?