just saw this post today. But I have a JTV69 that has no serial #, Under the battery compartment I found written with a Sharpee : Beta # 7 3/12/10 TW.
I purchased the guitar from a journeyman guitarist (C. Witt) I was told that this was a US built prototype by Tim Wilson. I sure would like to get some confirmation of this.
Mark Fawcett