Pyramidal Frustums Problem!!

Hi everyone,

First post here and a grasshopper novice looking for some help!

What I am trying to do is create a pyramidal frustum object that will be used as a floor slab for my building. I have the basics down thanks to tutorials and a little experimentation but I am now stuck.

The initial boundary curve (Outline of the slab) is there but the frustums themselves are not constructing themselves within the boundary. I am working off an 8m x 8m grid for the building with each 8x8 grid having 10x10 800mm frustums within it. I can play with the number of frustums later on as they are not to the correct size at the moment as my computer runs slowly when there are too many to deal with.

What I want to do is to create a hole in each of the angled lofted faces (all 4) to allow for services to run through them. It will look like a waffle slab but with the services running through the slab instead of being suspended below.

So what I need help with is building the frustums within the slab boundary and creating holes in lofted faces to allow services to run through them...and if there is any way to cut holes into the 'slab' when finished for service cores (I will probably need to do this in rhino afterwards which is fine) that would be great.

I have added a picture of what is happening and what I want to do. the yellow highlighter shows the inner boundary I need to work within and the outer line it is currently constructing to, and the blue are the holes I want on each of the frustums while the black pen shows where the services will run.

If I am being unclear/wrong terminology let me know and I can try to explain more clearly.

I am really stuck with this at the moment and it is very frustrating as it probably doesnt need that much changing (i think) but I am not sure what and where.

Thanks and I look forward to hearing from you!!

Sam :)