Suppose you are designing a tall bookcase. It consists of a base approximately 4" wider than the box containing the shelves, the box and a top the same width as the base. the base is about 5" tall and the top is about 2" high.

If you wanted to apply the Golden Rectangle to this bookcase design, would you apply it only to the box that contains the shelves or to the outside dimensions of the overall piece.

In other words, if there is an overall height in mind, would you take that height and do the math or would you subtract the heights of the base and top first?