Abstract: A guide module is provided for connecting a primary circuit board and a secondary circuit board to a common backplane circuit board. The module includes a body that has opposed top and bottom surfaces. A locating feature, on one of the body top and bottom surfaces, establishes a stack height for the secondary circuit board with respect to the primary circuit board. The guide module includes a front face defining a plane that is aligned perpendicular to a mating direction of the primary and secondary boards to the backplane board. The locating feature includes a raised fitting that has a centering rib on an outer perimeter thereof. The raised fitting is received in an attachment hole in the secondary circuit board. The locating feature also includes a boss that has an upper surface upon which the secondary circuit board rests when coupled to the primary circuit board. The upper surface of the boss establishes the stack height.