Kenneth
1 AYC Bar
Below is a picture of series 1 and series 2 ignition coil plugs. As can be seen, series 1 has the bigger gaps, the series 2 is a little too small for the inserts on the COP adaptor plugs. It isn't off by much, but just enough so you can't put them together without removing the inserts (which doesn't seem to make any difference anyway)