Wow! What a great write up. Good job. Very smart. That's my kind of thinking. Probably should show a pic of the nuts and coil adjustment in a close-up or two.
That's the bench test I was speaking of. A VERY nice description of a bench test
Member DADS50 also has pics and a video of his bench test. Did you in fact adjust the coil and did it make a difference?

Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn