Chainsaw Repair

I don't know how critical the air gap is? But I finally remembered to check it out with my micrometer. I checked 11 different business cards and a doctors appointment card and they varied from .007" to .0165" That is a .0095" swing that is almost ten thousandths, that is a lot. I did finally find one business card that was dead nuts .012" I suggest you mic your air gap business card and find one that is at least close to what it should be. Like I said I mic'ed 11 business cards before I found "one" that was good. I also thought I would try a plastic drinking water bottle because it was rounded almost the same as the flywheel so I cut one and it mic'ed out at .014" I don't have a pie cover yet. I only found one business card that mic'ed out to .012"
I also cut open a aluminum Pepsi can it was .004" I wanted to try and find something that is already rounded like the curve of the flywheel.
If the book told you to gap your spark plug at .020" would you be ok if you set it to .017" or .023"?