Well we got the narrowed 9" rear end back and now I have some serious clean up to do before Marty fabricates the four-link rear suspension. I'll be deburring it and cleaning up both the factory welds and the welds made in shortening it before it goes back to Marty's. I'll also be cleaning up the backing plates and rebuilding the rear brakes with new parts and ordering a set of new cut-to-fit axles. The measurement from flange-to-flange is now 51". We took about 8" out of the Ford Bronco 9".
Here are some shots of the clean-up effort in progress.