I have a 1990 Mercruiser 5.0LX engine with an Alpha I outdrive. I want to replace the Thunderbolt IV ignition system. I was told by a MSD distributor/rep that there isn't a MSD system to replace that ignition with. The problem is the shift kill switch. When shifting out of gear the drive needs the engine to be momentarily stalled in order to release the shift dog. If the engine doesn't stall/hesitate the drive wont release and the boat will keep moving foward. Is there a diagram that shows this installation? I was thinking about hooking the negative side of the coil to this switch. I was told by the MSD rep that this would ruin the coil.