extract geometry from solid model

Hi,
I'm loooking for a way to extract all the geometry of a solid model and
project it onto a plane away from the solid model. I want to do that in
the model space.
I would dimension and put center line on this one-plane geometry and
hide the solid model to make sure I don't snap anything on the solid
model who is behind.
I know there's an option to get all the dimensions to stay on one plane
even thought you snap things on different plane but I really do want to
get the geometry extracted as well. The section command doesn't do the
job since it only extracts the stuff that crosses the section plane. My
3D parts a way more complicated. I would need to make 10 sections and
copy them on one plane and it's long and not efficient.

It's kind like exctracting all the geometry of a previous feature in
solidworks and use it in a new sketch.

I used to do that before on Autocad drawings I have but I don't
remember how I did. How can I have a kind of script file of all the
command I used to create this old drawing. I am quite sure it is
possible.

Thanks in advance
JC