Battery Question

Okay, I am to the point of mounting my battery, and making a tray. The battery that came with my truck is 10x7 at the top, and 10x8 at the bottom wihth the new style mounting flange. I need a battery that is about 10x6.5 at the bottom. So something without the flange would likely fit. I don't want to relocate the battery really, and I don't want to spend $400 on a battery. I'd go for an Optima, but does anyone have one they canb measure? Top and bottom? The site says 6.8", which would work if thats the measurement of the flange. Any ideas?