this thread is too promissing to be true. allow me to stand back till anything, just anything, is confirmed and released, then i ll applaud..
in the meantime if you are serious - the homepage of georg braun who created gba1k and consorts is here:
http://www.gb97816.homepage.t-online.de/he has released documentation what concerns at least part of his projects, i dont know how much exactly. but you can contact him.