I don't see a problem with running the box flat, it wont hit the box frame as you swapped it over to tube like they normally do.
But what I do see is your approach angle is going to suck, no offence. Why is the Rad. so far away from the motor, I know you need room for the electric fan/fans but it seems like a lot or room in between there.
To me you can come back almost 6-8"s and that will still let you drop the winch in its hole and can make the overall of the front clip close a foot smaller.
Maybe you have other plans for the space, but unless your running 42"+ tires your bumper will be eating everything up front first.
1993 YJ 4.0 60 Front, Rear steer 60, bolth spooled, 5.38's, 700r/241 39.5 iroks and beating it like it owes me money.
And on the 8th day, God created the 14 bolt....