I have always just "tubed" it where the U bolts go through. Put the back brace on, mark where the U bolt goes through, drill it and install a tube welded on both ends...or not. Doesn't matter as long as you don't drill into axle tubes. Yes, you will likely have to do lower shock mount work to keep the shock off the brace.

Those mounts shown above are really nice, although I think they are a little tall. Regardless, your lower mounts need work. Stock pads will just fold up on a hard leaving car, so they at least need to be braced up