Mike read May 2010 VA Bulletin clearly states from 1961 to 1975 duty in Thailand you are covered for herbicides exposure per VA. Sounds like your mos also clearly defines where you worked. Gather up all the proof on the internet that shows where your duty work area was. Use any maps and photos you can find. This website has a great pool of airman on it with there emails for buddy letters. More and more claims are being approve on Thailand exposure but proof of perimeter duty is the key. Just look forward to the day of your appeal hearing, and good luck finding any helpful info. Steve