69 Transmission Identification

[SD stang]

hello everyone,

I am new to this site and to restoring cars. So go easy if the answer to the question is obvious.

I recently purchased and 69 coupe and everything removed from the car and placed back in the car. The car itself is fairly complete becasue I removed all the items and most of the major components are there.
now my question

I found the transmission and cannot tell what it is. The Body Code of the car says that it should be a 3-speed manual transmission, but the person I bought the car from told me that it was an automatic. If there is some obvious way to tell an automatic from a manual, if there is i have no idea. So can someone tell me what to look for or what sets them apart?

thanks for your help :D