We stock the Screamin Demon 40,000volt coil and Live Wire Leads as raved about on this thread!
No interference problems etc with this set up . We keep it all in stock ,the leads we have in blue or black. Its nice kit (thats why we stock it). We always run it with NGK Iridium Sparkplugs at standard gap. Nice & smooth, no misfires economy possibly a little better? Emission lights stay off more too

, so must be doing something.
BTW the suppression is in the plugs on the Mini (R=Resistor,) so interference could be a poor connection or a plug fault?
Best Regards Roland GT Tuning