Randy you seem like a do it once, do it right, kind of guy... so here's my recommendation for the battery tray: http://www.stainlesstrays.com/
however your big arse batteries are probably bigger than the optimas, so you may not be able to use the bottom clamps like they have, but I bet you can fab something similar. I sure like those though, what a clean way to do it..
and I envy in a 40 how you can put both batteries right next to each other, sure makes the wiring simple, nothing running across the firewall, behind the radiator, etc. like us big wagons have.