you could always run it inside the cab and cut a hole in the roof, and seal both ends, you a section of flexable exhaust tube/pipe for the the allowance of flex between the body and frame. like basically go from the turbo up to the body, and just before you enter the cab, put that flex pipe in, then you can seal up the holes at the floor and roof with rubber seals and silicone. you can run it at the same spot as your pic, just on the inside. that way you dont have to worry about vision... just a thought i had...