It has to be an "R" series battery to fit as the "R" stands for Reversed (terminals). I have a 34r going on it's 3rd year in my truck.
And...they make lots of Optima boxes to fit the battery/truck that aren't machined billet and don't cost $100+. I have a Blue Torch Fab box I paid $40+ shipping for.
my machined tray is purty tho...