Resistor ends, if you had bad ones, would account for the smoother idle. The 0.045" plug gap is a bit wider than usual(I like 0.040"), but real close. I think we've discussed the theory here before,but the point is that the wider gap uses a bit more of the stored potential current from the coil. It makes a larger/hotter spark. That is a good thing. The down-side is that the later style small coils don't have a lot of reserve, so I wouldn't go wider than 0.040".
If you're going to use NGK plugs, put a bit of anti-sieze on the threads. They don't have the nickel plating like the Bosch DCOs.
Regards,
Randy D.

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