go to embassy, fill up documents, digital sign, they make pic, pay, ask them to sent you the passport, (80 bahts), you will receive at your home 3 to 8 weeks later, you will receive 2 EMS mails, one with passport, other with codes (just 1 hours in bkk embassy then he can go home)
ah ok thanks now I know. That's fun as its 25 years on retired and I did not know ! (before it was 12 years on marriage visa & I not remember I changed something).
also in case the wife die, it must be reported, i still not sure if it happen to me (marriage & retire). in fact i have no idea the extension i have... lol.