Just quickly harking back to the "GG" issue, although the lack of info regarding this production line could be taken as worrying when considering the guitar's integrity, I can confirm that my version (which is a Dove) is definitely a genuine Epiphone and has been built particularly well!
So, for those that are here researching the GG serial number, as I did when i came across this forum, don't necessarily be deterred the guitar just because it doesn't show up on the guitar dater project system.
Thanks