These are the plug wires you want to be sure don't touch #7 and 8), because you can get induction firing under certain conditions, and if this happens at wide open throttle it can really get your attention. You'll note cylinders 7 and 8 are right next to one another, and so are the plug wires, thus the danger. One plug is all powered up and ready to fire, and ooops, the spark jumps to the other wire and BANG, you get a pre-ignition.
As for the slight miss, this could possibly be the cause. I've recently been sensitized to plug wire resistance, and I've been checking my old wires with an ohm meter. Sure enough, some of them are really poor. Tim Toth recommends the spiral wire wound plug wires, which he claims have the lowest ohm resistance in the market. Low ohm resistance means all the spark energy gets to the plugs.
If you have conventional points and condenser, I'd suggest changing out to Pertronix electronic modules. It's the nicest thing you can do to a 427. Also, check the valve clearances, if you have them set too tight, it will run rough and you won't generate full power at higher rpm.
Here is the thread to the Pertronix Ignition info
There are several such threads in the 427 section of the MASTER INDEX, which I believe you will find very helpful and interesting if you own a 427 (including a section on plug wires).
These are the main issues I'd go after for the "slight miss" symptoms. Good luck!
Here is where you can find plug wires #7 and #8