Lining up the outside flange of columns and keeping them in line ..

When modelling portal frames for example and you want the flanges of the columns to line up regardless of the column size or if the column size changes.
The trick is to use a reference plane and lock the flange of the column to this reference plane.

Let me try and explain.

Put in a reference plane, say, 160 off of grid ( the trick is to PIN the reference plane in place ) and then place your column and align and lock the flange to the reference plane.

Now if you change the size of the column the flange will stay aligned and locked to the reference plane.