Classic/Antique Car Repair: 1951 chev p/u with 235ci, volt coil, metal core

Question
My ignition system is not working correctly.  I was running a 12 volt coil with a resistor to bring volts down for the ditributor, but recently changed to a 6 volt coil.  Have new leads plugs and wires.  The problem is that at night you can see the plug leads at the plugs glowing, and the coil is arcing from - and + to the center of the coil.  I have done all I can but can't figure it out.  The arcing also occured with the 12 volt coil.  hoppppe you can figure this one out cause i'm all out of ideas, thanx chris...

Answer
We used to call the glow around the ignition system corona, and most of it was normal. The arcing though has me a bit concerned. I think that I would want to make sure that the plugs were gapped properly at .025" and that they were straight run of the mill plugs and not resistor plugs. The plug wires should be the plain old copper or metal core and not resistor wires. Any resistance in the secondary system will increase the firing voltage and could cause leakage. Also make sure that the rotor gap is correct and that the center contact button in the cap is OK. Then see what happens. Good luck.
Brad