Here is a CMI (long C, like the amps), Marshall-imported lead/bass twin-neck SG/EB3 copy.
Nicely done, even if bolt-neck. Has the “Steel reinforced neck, Made in Japan” plates that, IIRC, others with better knowledge say is a Matsumoku identifier.
Sorry to have vanished, especially as some really useful knowledge has been added instead of my guesswork. That lefty cMi LP interests me greatly.
http://i.ebayimg.com/t/CMI-Twin-neck-1970s-6-and-bass-/00/s/MTIwMFgxNjAw/$T2eC16F,!zcE9s4g0uu-BQdVcz2POQ~~60_58.JPG