Just to add some history. Since day one this engine has seemed to have electrical issues. With points system, fouling plugs #8 and mis-fire. With Pertronics system, engine breaking up, mis-fire under load fouled plugs. Added fuel pressure regulator as suggested to use with edelbrock 1406 carb set at 5psi. and no more fouled plugs. Still have mis fire under load. Which brings us to present day. All this seems to indicate there is a electrical short or something wired wrong. Thanks all again for your help.