Abstract: A multi-core plastic optical fiber is used for multi-channel communication purposes. An alignment tool comprising a light source, selective filter and a detachable alignment-tube having a guide notch is provided to map the individual cores of a multi-core plastic optical fiber and prepare the connection of optical transceivers to both exposed ends of a pre-cut length of fiber. The alignment method results in a pre-cut length of fiber having alignment-tubes with guide notches secured to both ends. Transceiver guide projections mate to the notches, creating a complete optical multi-path between the transceiver active elements through the fiber cores. An automatic method of assembling optical transmitters to a multi-core fiber and mating optical receivers uses no alignment tools and tubes. This method dictates a specific placement of the optical transmitters in relation to the cores and receivers, assigning each transmitter to a preferred receiver based on detected light signal criteria.