Grasshopper "Rhino" tools, Dimensions Offset?

Hi,

I wonder how I can use the Grasshopper “Rhino” tools to create dimensions with an offset? Nothing I have tried has worked so far, and the dimension stays right on top of the line in al cases?

I tried adding values to the various “Extension” parameters, but nothing seems to affect it?






side note: the popup tool tips are really not very helpful on these Rhino components? Most of them just repeat the name of the node. It would be helpful for these to describe what the inputs are supposed to be and what type of input they expect. Sure, I can fiddle and eventually discover that “Arrow 1” expects an integer input, but better help text would go a long way I think:

thank you!
@ed.p.may