I feel stupid posting this simple problem I found, but #2 wire read open. Not just a lot higher resistance than the rest, open. I made an old wire fit and it seems to be about 99.9% good. The a/f meter stayed more steady than it was. In 5 minutes it did miss a couple times, but nothing like with the open wire. I dissected the open wire ends to check the crimps and they are fine. Where ever the break is it must be close enough for the spark to jump it most of the time. I may have to dissect it all the way out of curiosity. The a/f meter is a nice tool for something like this, I think some time I will weld a bung on the left header reducer and swap the oxygen sensor to see if that side stays as steady, or more steady? I always thought the movement of the oxygen sensor was due to the carb not being perfect, but it's very steady now. Who needs EFI with a Quadrajet up top?