Man, I can relate to that... It's unfortunate you had to switch back to gas from E85 due to availability, because you can get away with cruising a bit fat on E and it won't foul plugs or run dirty. I battled my cruise AFR a few years ago, trying to clean it up. Just like yourself, I had idle and WOT dialed. I went down on main jet, but as I suspected, I was cruising on the idle circuit, so going down on primary jet didn't do anything. I had to restrict fuel to the transfer slots by reducing the idle feed restrictors. I measured mine, they were pretty large at .035" (as it came from Holley). I got blanks and started at .025" and the car was coughing on cruise, too lean. I'm almost positive I landed at .029" for my car. If your car is just fat on the gauge, but is cruising smoothly and without fouling plugs and hiccupping from being too fat, I'd almost be inclined to leave it, if you can live with it. But if you're like me and you gotta make it right, the above was the right path for me.