i'm not a purist when it comes to what's in a battery box .. i don't even use the oem holdowns anymore, just wood , polyethelyne, or styrofoam blocking to keep them from moving around .. rough off-roading would be a different story though.. Thus for 30 years i've used any pair of good 700-800ca top-post batteries, even in the 5-tons, multifuel and diesel versions... in winter i have run 4 batts in the most-critical trucks, especially the cummins' .. But my 2-1/2T's have always fired up in winter with just a good pair of 700's etc