I also have have a wilson guitar serial number jt-4 that i just dug out of my closet mine reads wilson and sons model jt-4 made in japan 1971. I bought this new from a music store in ontario California. I was in high school at the time . I also wonder what its worth. I don’t know what we paid for it back in 71 let me know if you ever found anything . thanks now residing in rancho cucamonga California ..