@Bob **********
Okay in Chiang Mai you can apply for the initial 90 day Non-O visa for 2000baht when you have 45 days or less left on your current stamp (30 day entry stamp, 60 day tourist visa stamp OR 30 day extension on that)
AND
you need a minimum of 15 business days left on that stamp to do it (really that's 21 calendar days) 🙂
There is no requirement to show the funds came from abroad OR that they were in the account for 2 months when you apply for the 90 day Non-O visa
you need to GO to the Chiang Mai immigration office and get the list of copies, TM30, map, bank letter, bank book update, etc you need to apply for that visa because with 30 days left on the stamp you have you got about 9 days to get the application in or you're going to run yourself out of time