Looking at the dates you were one lucky dude. Vietnam Nam was raging. From what I heard a lot of the guys went to Panama for 6 weeks to acclimatize and train in the Jungle at Ft. Sherman before they were shipped to Nam. The still had the zoo at Fort Sherman when I was there. They had an anaconda that had escaped from a crashed plane that they had caught in their jungle. That thing had a head the size of a basket ball and was over twenty feet long. That is a lot of snake!
I believe that was for the special forces or Green Berets.
In May, 2016, I briefly played senior softball (I left for another team) with a black guy who claimed he was special forces in Vietnam and that he was training in Panama in November, 1969 when I arrived.
The guy was a bull shitter and the more he talked the more I began to see thru his lies. He was two years younger than me and at the time I arrived in Panama, I had just turned 19 in October so that meant that he would only have been 17 and impossible for him to be special forces. At best, he would only have completed basic training if he enlisted after grad. from HS in June of that year.
That July, we saw his picture on the local TV news. He had just been arrested for impersonating a federal officer. Turns out the guy had a criminal record and had done 3 years in prison and was released in Feb. of 2013 for the exact crime. The arrest in July 2016 netted him another 3 years in prison...................LOL!