[HDChvyTrk]

I think I would point the finger at the ignition system. If it is not smoking but fouling plugs quickly I would not think it was enough to rich to matter? I would think about a good coil, like an MSD Blater II and maybe an MSD 5 or 6 series ingnition box. This will help your ignition produce a stronger spark. You may, at some point, want to consider a distributor swap also. I asume when you say " the original distributor" you are refering to a single or dual point distributor. If so, and you want to try and keep this setup you should look at the points, replace and/or gap them. They control coil dwell (charge) time and could be a major part of the problem?? If you have a HEI They are famous for frying modules and you could also check the little nub that sits under the coil that transfers power to the rotor.