Selecting and moving specific polygons in Grasshopper

Hi,

With a lot of help of the forum users I am getting forward on my personal project in Grasshopper.

I would like to make a last tweak to the model. I would like to modify the height of the cubes by selecting the upper lid polygons and moving them in the z axis. I could also scale them in Z but I would like to preserve the bottom and lid quality:

I tried to do first that on nurbs and then apply the wavebird plugins , but I get too many polygons in the yellow are (pic above) that I do not need and make the model extremely heavy.

I would like to preserve the quality of the top and bottom and get a simpler polygon calculation in the middle of those.

Is it possible to manipulate these after transformed to polygons with Wavebird subd components ?

Please find attached the file.

Thank you a lot.

Candies2.gh (43.4 KB)

missing

Yes I am using the human plugin in order to have different heights on different layers.
But you could ignore it, the mesh part comes before. Also I am using lunch box…