If they are stacked one over the other, it's hard to view the contents of the ones in the behind without moving the ones on the front.

But to make things easier, Use the Document Outline window.
In the Document Outline window, select the groupbox you want to view. Notice that the particular groupbox gets selected on the form. Right-click on it (top left corner) and from popup menu select "Bring To Front".
This way you won't need to move the groupboxes.