skip white HEI timing issues

Sure, we need to find out when this all started. Was the engine running OK before the changes to the ignition system? I think I read that he said the scatter was present before he changed the dizzy.
What other ignition parts dose he have handy to swap out and maybe be able to pinpoint where the problem is.
As posted earlier, too soft weight springs will cause scatter and erratic idle with a larger cam profile.
If it's scattering at higher RPM then I'd be looking at the ignition system first off.