Just to add emphasis to what Clint is saying. One rotation is just shy of .036", 1/8 of a turn is just shy of .0045". Getting to your desired tension span with required alignment maybe in very small increments of shim thickness. You would never want to use an individual shim that adds 2/3 or less of rotation to a base shim. You want to use a individual shim ideally, or a combination of shims that are thicker than 2/3 of a rotation. When the shims get too thin, they can fall into places that can cause all kinds of trouble.
As for the prior post on the KAC MOD2 11.5" gas port size. I hope that is a measured deviant rather than a newer spec. Deviations happen during manufacturing, KAC does like to drill holes. Not my ideal way, but I understand why they chose their process and I'm fine with it. It's also possible that they changed some other things that would require that port change, it's not a huge difference no matter what. I can't drop a .070" gauge in any of mine, with one exception for their legacies, Christmas Cheers, MOD1, or MOD2 barrels. One MOD1 could drop that gauge, but that particular one shot accurate enough that I would rather mask it with a step up in buffer mass than send it back. That example was only one of very many without that issue.