For what ir is worth I am 6'2" (188cm) and my shoulder is approximately 4'10" (142 cm) from the floor. If proportions remain the same the soldier on the left would be somewhere around 6'6" and the soldier on the right around 6'. While certainly within the range of possibility the 6'6" guy is pretty darn tall for WWII.
Are the belts suppossed to be the same? They look to be differnt widths. How close are the holsters?
if the gear is the same size and both seem to be proportioned well I'd say you CAN use the both next to each other but you may not WANT to use them together.