I have been searching for years, but have yet to find much useful info on production numbers---I did find a site that seemed to have fairly accurate production dates (lost the link) My guitar is S/N E1774, and was built in late 1974 (first year), and I have seen some for sale with a 5 digit S/N. The early models had the torroidal pickups which were much hotter than the Humbuckers in the later models (mid 1975 or so was when they changed over) It's a shame nobody seems to realize that these old beauties will SMOKE a Les Paul or a Stratocaster for ANY genre  I have owned mine since she was just a toddler (1978), and will NEVER sell her! These guitars were WAY before their time, and they are more versatile than any "modern" guitar!

Messina Deacon.... 1