Hi Booleano, I'm sorry but I'm not understanding very much of this.

First off I'm seeing 6 objects in Green, not 3 like you wrote and the objects are stacked up on top of each other.

Next thing is I don't understand what you mean by doing a boolean difference to a specified dimension. Is it a 4mm radius fillet that you want to have that you are showing in CC.jpg ?

- Michael