an apparatus for intergrating plural printed documents into a stacked relationship , such as a magazine , catalog and the like . the apparatus includes a printer for applying customized messages to the magazine , such as the inside cover . this printer is controlled by a controller located remote from the assembly apparatus and at a distance exceeding 150 feet from the printer . a communication interface is provided comprising a line driver / receiver interface for amplifying and shielding the signals required to control the printer , preferably signals indicative of the document position of the document with respect to the printer . a non - standard data format protocol is maintained , and the interface is transparent to the apparatus . the controller is located within a control room with an acceptable environment for operation of the controller , this environment having an acceptable temperature and humidity .