Update 2
Alright, verdict time.
Was at the range on Saturday, had a chance to shoot it and here's what I found.
On the positive side:

Consistency was good. The groupings were predictable and regular.
The setup returns to "zero" after being removed and reinstalled.
However:

I ran out of left adjustment, at 200 I was a mean of 4" right and was at approximately -1 1/2 full rotations (left) past the marked graduations on the turret. Pretty sure this has more to do with the installation of the rail than anything though.
The eye relief is gawd-awful. In order to see through the scope I had to be shooting off elbows so I lost a lot of precision.
The shell-deflector I built is: too short, so casings were still hitting the scope, and too sharply angled, so I would get a case back in the breach every 5 or 6 shots. This was my own damned fault though.
Lessons learned:
1. It is totally workable. (If you mind the following)
2. Installation of the rail must be mindful of alignment. There is more than enough play to run you out of scope adjustment.
3. To avoid shell impacts a deflector should be as shallowly angled as possible and extend beyond furthest extent of the scope's turrets.
4. Eye-relief, Eye-relief, Eye-relief! If your scope it sticking back over the stock: Forget it. It's way easier to choke forward than back.
My conclusion is that once I get the rail lined up right and have some more reasonable glass and build a better deflector this will be a pretty serious setup. I knew coming out of the blocks that the scope was wrong for the application and would probably fail out, but I can say confidently that there's a ton of potential to this setup.
The challenge is that I get the rail aligned correctly and I find glass that properly suits the application. After I get it dialed and some nice optics I'll be back to show everyone what she can really do though. It's gonna be sweet.
