I'm sure folks wish we would keep better track of things like when the A mark started showing up on the back, but it's just one of those countless decisions we make every day.
I vaguely remember drawing an enormous A for the artwork on the tuners when we were still on Foley Street, but it had to be after 1987, because that's when I started working here. In 1986, it's almost certain the tuners were chrome standard issue Gotohs, which except for the decoration are the same as the Alembic-Gotohs.
Another note about tuners We received many compliaints that the tuners didn't match the brass hardware. Sometime after 1987 (probably before 1992 or so) we started putting gold tuners on as standard. We loved the chrome finish for it's practicality - it looks new for a really long time, unlike the gold, which can wear pretty quickly depending on the person.
Hope this can help clear up questions about tuners on Alembics. If there are others, please ask myself or Valentino, we're happy to assist.