Elevation Set Crop Box issues

Hi All;

I have a bunch of elevations that I want to set only the elevations of the crop boxes programmatically.

Essentially, user selects an elevation - extract the level name from the elevation’s name (based on naming convention), change the crop box so that the top is the floor above and the bottom is the level below.

I can extract the level name, all good. I can then get the elevation of it, and the level above. I grab the bounding box of the elevation that is selected and a quick scan seems to indicate that the Y co-ord of the crop box is the vertical range of the crop. So I was extracting that to points and grabing X and Y of the min and max points and then creating a new set of points using the elevation of the two floors… and I get “Item cannot be null” when I try to set the crop. See attached.

I am very new to Dynamo, but from what I can tell, I have a bounding box on the input to the node, and I have a valid element on the input to the node… so I am stumped.

I also attempted a variation where I intersected that bounding box with the original bounding box… and that rotated and shifted the whole elevation - however it did set the vertical size of the bounding box to the correct location - it was just not looking in the right place any more.

Any help would be really appreciated.