Rule based morphology

Hi Team,
I am intending to create a rectangle in between line segment 1 and 2.I would want to create a rule such that the rectangle should be formed only when the distance between the line segment is 8000mm.if the distance between the line segemnts is less than 8000mm there shouldnt be a rectangle formed.Eg In the below attached image we can see 2 line segment 1 and 2… the distance between these 2 lines is more than 8000mm hence a rectangle is being formed.Now consider line segment 4 and 5 the distance between the two is less than 8000mm hence no rectangle is being formed.Please could any help me out with scripting this kind of logic.I have attached the jpeg and the grasshopper file for the (10.1 KB)