Once you get an extension (either 30 days OR 60 days) you can apply for a 90 day Non-O visa based on marriage to a thai national at the Chiang Mai immigration office. You need 21 days left on your current entry stamp to do it, (which is why I covered how you can get an extension FIRST in #1 and #2)
2 - go apply for a 60 day visit thai family extension on your 30 day visa exempt entry stamp at the migration office for 1900baht based on marriage to a thai national
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