If it don't fit, make it fit! Right now I'm making a bumper for by duramax using a timing chain out of a big diesel electric engine. I'll post it as soon as it's done and painted.
Think about a stock bumper, and how thin it is. Even with the rolls and bends, it's dinky, but strong. If you cant get away with 3/16 and 1/8 inch you're gonna tear up the front end of your rig.