And here I was thinking that you guys endure excruciating pain only on the up!
Seriously though, sounds like we have (or had, in my case) a very similar problem.
When I told my boot guy the problem, he took a quick look at the shell and could immediately see how it curves in, almost forming a little shelf.
Modifying it while still preserving the exact alignment of the latch bar is definitely the hardest part.
Some pictures (of my left boot) here.
If you local guy can't do it, then try Greg Hoffmann -- ...