[Christ]

You're going tank by tank and testing mods with each tank?

Why not try eliminating some variables and running each mod for more than one tank?

If you get a 5% increase from a mod, with your 22mpg, it's only going to equate to ~1mpg, Mike.

You'll likely dismiss it as "noise", but you'll have a better test bed if you had some sort of instrumentation that could quantify changes in the way your vehicle operates, even a vacuum gauge. IF you're getting better MPG, you should notice lower vacuum numbers while cruising.

Stickers is remarkably clean underneath, by the way.