HELP!....Boolean problems

Hi

I am having problems boolean two "diagonal grid polysurfaces" I made in grasshopper then baked.  I have only been using gh for only a few weeks & I was wondering if someone could help!!

I have two twisting diagrid towers which collide.  My aim is to remove the colliding regions.  I created a solid mass (which has the same form & shape as the diagrid) as a subtracting surface in order to cut the other diagrid.
Iv tried using the boolean difference & spit commands.  Both have failed.

The Rhino file is quite large (330mb) so i have attached a photo instead.

Much appreicated!

Jason

PS:

As a seperate issue.  The geometry don't interesecting properly when the dia grid towers meet. Could anyone give me adive regarding how I could rectify this??

Thanks in advance.