DFR0016 - Assembly

It might seem obvious, but not to me. What is the precise placement of the headers on the DFR0016 prototype board. I am mounting an LCD panel on top, and it uses both vertical and horizontal sets of pins, so alignment is critical. I understand that the horizontal pins must be fixed to the lower of the 2 rows of connectors, but I can't seem to position the 2x18 header such that the LCD pins, both vertical and horizontal mate. I'm beginning to think it isn't possible.