Really interesting thread. I have two sets of brackets; one from the older series 1 suspension and the other from the XJS series 2. I bolted the newer set to the series 1 diff simply because they were easier to clean up, but this thread has me thinking about double checking the hole measurements just to be sure. The diff sits perfectly level on a flat surface with the newer brackets, but the top mounting surface slopes forward visibly about 5 - 7 degrees. I know that the control arms were parallel to the ground before, so I may end up having to restore the old brackets.
No idea why the photo is rotated 90 degrees.
EDIT - The shiny area on the case just inboard of the caliper mounting bracket is one of the spots that I had to massage with the Dremel tool to create clearance for the caliper mounting bolts.