Was back in my local costco and sure enough they started carrying the 6V again. I asked the guy working there why they had stopped and he was not sure but they had 10 in stock. Picked up 2 and am currently in day 3 of a boondocks trip as I type this. What a difference from my single size24 marine batt. Ha! Nights right now are ranging 37-42 so the furnace runs plenty over night. This morning the battery reads (at least according to my in command system) 12.1v which apparently is around 60%. My old 12v would have been totally dead by about 5am. I run my generators a few hours in the afternoon to recharge and so far so good. Time will tell but thanks again all. This will make boondocking life much easier!