There has been, so far as I know, no real attempt to map the debris fields. I don't think that such a survey would reveal anything of real value; even if one could identify and locate each piece in the debris field individually, it remains unclear -- at least to me -- exactly what useful information might be gleaned from that.
The ship was pounded on the surface for quite a while, and a fair amount of material was no doubt blown overboard (and scattered all over the place) during this phase, from both projectile and torpedo explosions. Later, as the ship capsized and sank, a very great deal of additional material detached itself and marked an area on the bottom which is probably directly under the actual sinking point. Later, as the ship struck the bottom and slid down the slope, a great deal of material -- mostly from the shell sides and bottom -- was detached. This, plus bottom impact damage, unfortunately erased or obscured much of the evidence regarding earlier torpedo hits.
I have not, in general, found debris field mapping to be very useful. The debris fields from Titanic, for example, reveal lots of interesting internal artifacts from the ship, but give only the broadest picture regarding her structural breakup. Someday, I would like to go over Hood's twin debris fields to see if I can determine -- confirm actually -- that one was due to the after magazine explosion, and the other was due to hull breakup as the ship plunged.
I do recall finding what appeared to be a complete turret back during the 2001 expedition, though I don't know if it has been relocated since. I have a vague recollection that one of the turrets we found on the bottom is missing a back as well, which would confirm eye-witness descriptions. Whether or not the loss of the backing plate would cause the turret to tip forward is problematical, the rotating structure goes down quite far inside the barbette, and would probably jam against the inside surface of same before much exterior tilt was evident. I'd have to check the engineering drawings of the turrets to see, and even then it would be very difficult or impossible to do more than a rough estimate of exactly what would end up bringing the tilt up short. If the turret tilted at all.
Hope this helps...