I have a Gibson with what looks to show ES 125 T inside the f hole. Then on the back of the neck it shows 36417.
It was my dad's and all family said he got it when he was a teenager. He was born in 1938. From the info in this thread it could be a 1958 or 1961. So confused on the info, neither makes him a teenager. I also have the Gibson Amp that was bought at the same time. I haven't found a built date on it yet but haven't really opened it up.