I have a very complex solid body to play with and the area of interest is just the "bottom" surface. I do not want to use the mold tools for finding the core and cavity surfaces, but I would welcome a quick way to select what I need.

The funny thing is that the Draft Analysis does the job 99.9%. It colors the bottom faces in a different color and also allows me to hide any face colored otherwise.

At this point would be nice to be able to do a "select all faces visible" and knit them in a surface. For that, I hoped to be able to either hide the other faces and select all the visible ones, or use the Power Select tool to select only the red faces.

Unfortunately, the Draft Analysis tool does the coloring using the GPU, so really, the faces are not colored in reality. Same for the hidden faces. They are not hidden from the SolidWorks point of view, since they are selectable. What about having an option to save these colors in an new display state?

Any other suggestions?