the corresponding diagram. GM used 4, 5 and 7-pin modules in these distributors. NOTE: Some 5-pin models may experience a hesitation or stall on deceleration. If this occurs, contact MSD Tech Line for the required bolt-in diode to correct the problem. MSD Tech Line (915) 855-7123. Related searches for msd 6520 wiring diagram msd 6520 instructionsmsd 6 plus wiring diagrammsd digital 7 wiring diagrammsd distributor wiring diagrammsd digital 6 instructionsmsd ignition digital 6 plusmsd 6al plus instructionsmsd digital 6 plus installation