My 16 year old son is considering a sex change operation and moving to Thailand for both the
procedure and possible employment. As a parent I'm conflicted. Advice?

There is an awesome documentary series that's simply called 'Ladyboys'. I've mentioned it here before and stated that in my opinion it's a MUST WATCH!

It highlights both the 'good and bad' sides, but in particular, the fact that this is a one-time operation and is NOT reversible. Many Thai boys, who have essentially grown up as a 'ladyboy', saved hard for years in order to have this operation and given it lots of thought and consideration, often go into deep depression, even suicide, during the years that follow.

I strongly recommend you find this series and watch it. More importantly, get your son to watch it.