I had totally missed that part or read it and it didn't register.

There's no way I'd use either the angled wire in a box system or the Durant system in your case.

The biggest reason is the issues of installing either one in a rebuilding situation. Either systems would require major work and demolition to incorporate into an existing plane and for no actual flight benifit. Add to this the need for a very high degree of accuracy with either system to ensure that the servo axis lines up spot on with the hinge line or that the bend on the torque activator lines up dead on the hinge line axis. You just do not need that sort of extra concern in a rebuild. During new construction it wouldn't be so bad since it would be easier to arrange assembly jigs and measure alignment more easily. But on a rebuild you're not going to have a good way to ensure that amount of accuracy in the placement of these systems.

And frankly it's just more work to cut into an existing model for this than it's worth. Neither of the systems give you any advantage other than a visual one for neatness. And both bury the servos in a way that makes adjusting or replacement a total PITA. On a model of this size external horns on the underside of the model are all but invisible anyway. If the model uses surface mounted servos and you're just looking to tidy up the installations just lower the servos deeper under the surface so just the output arms are exposed. Just putting the bodys of the servos under a hatch or patch of covering material will make things look a LOT cleaner but still allow ready access to them for servicing. A far more sensible compromise all around in my opinion. Especially given the opportunities for damage to the servos from pushing around such large surfaces or if those surfaces should suddenly be leaned on by an external force. I don't fly the big stuff like these but it seems to me that burned out servos and stripped gear trains would not be all that uncommon on these models.