You have six coils stacked vertically and six cylinders stacked vertically. top coil should go to the top cylinder, the next coil down goes to second from top, 3rd goes to 3rd 4 goes to four, etc etc. At least that's the way it came from the factory. however if someone rewired the switchbox wires wrong or put the wrong wires on the coils(they are numbered by tags) or moved the coils around, all bets are off