Trimming brisket packers cut for UDS

I have been trimming all of the fat externally from my packers cut and placing the fat over the brisket which smokes in an aluminum pan. At 160 I put 1 inch of au jus in the pan and foil. This is my method on a 300 gallon ofset trailer smoker. I'm trying a UDS directly on the grate. How should I trim the brisket and should I leave the fat cap down, and should I wrap at 160 degrees until 190.