DoubleCurve Geometry via Projection.

Hey All, 

I have written a def to generate structure from a nurb surface via the mesh/plane intersection. So that I am able to set any structural grid on the YX axis, ie. this becomes the setting out grid. So this gives me the curves for structure and bracing - ie. pipe the curves. 

However I need to apply a component to this surface. I have found many defs online which use BBox & SBox via domain divide, however this def forces division in relation to the curvature of the surface (as I understand it) - the problem is the components no longer aligns to the structural gird. 

Is there a way to link the mesh/plane operations to the SBox - so that the mesh/plane defines the locations of the divisions? Ie. the domain divide is driven via the structural grid. 

Any help or input much appreciated. 

Cheers, 

Patrick.