Flipping line order

I have a follow up question:

I have this geometry/script that I’ve made with rotating elements. See photo.

I need these elements to be placed on the bottom lofted surface, and on that bottom only. See photo

How do I sort through the data?

Lotus buoy5.gh (43.9 KB)
moving elements.gh (14.4 KB)
GRASS_HELP.3dm (108.1 KB)