Thanks Max, great to see a successful test. That is what I did with the aftermarket coil. Turned it backwards. Seems really odd placing it this way and looks entirely wrong, but the results speak for themselves. I just left the STENS on Negative Earth. How about you, did you wire it to neg or pos? When I spoke to an auto-electrician a while back he said it won't matter which way I wire it.
Just a question, have you actually turned the coil right around, or just on its side, or doesn't it matter? It's just that I notice the brass keeper is not matching with the slot on the coil in your photo.