I use mine for hunting also, I don't know how much fresh water your rig holds. Mine hold 100 gls., I also run the hose through the waterheater for the extra 12 gls.. I hunt on the Georgia-Alabama State Line. I know the folks at the country store there, since i've hunting in GA for 15 yrs. So I just take a 150 qt. cooler, that i will use for the deer, and if i need water for showering, etc.. I just fill it up & use a 5ft. piece of hose that i use to siphon the water out of the cooler. How water depends on how many days, how many persons, if you take your wife or significant other (ladies pls don't get upset my wife likes long showers, no hunting trips for her). For storage put them under your rig like Big Al said. I think your underside should be heated, so get it close to the underside. Good luck on your hunt. I put 3 in the freezer as of this past sunday. Will return on mid Oct. for Black Powder.
Ivan