An optical mark recognition tabulation device includes a guide channel including opposing integral sidewalls configured to laterally constrain a test sheet as the test sheet is fed past a set of optical sensors. The optical sensors are aligned with optical entry indicia on the test sheet to sense marks on the optical entry indicia as the test sheet is fed past the optical sensors. The optical mark recognition tabulation device further includes a recessed channel located along at least a substantial portion of a side of the guide channel. The optical mark recognition tabulation device further includes a spacer strip configured to be received within the recessed channel and effectively reduce the width of the guide channel such that the guide channel is reconfigured to laterally constrain a different size of test sheet when the spacer strip is received within the recessed channel.