OK, five years later I did finally get this done.
I used a rusty panel without cutouts as a donor for the patch panels. ITs not perfect but it looks ok. I have the Dr Diff spring relocation kit and that may help a little but I cheated and added two vertical standoff supports at the exhaust hanger. These pull down on the lower valance just enough to give clearance on the shackle for it to swing. I do need to re-center the exhaust tips, maybe bring them back inside the valance a little as well.