Beatle Gear is an outstanding book, in my humble little opinion. I think it's one of the must have Beatle books, along with the Mark Lewisohn books. As for Macca and Alembic, I can't recall ever seeing him playing one. I've seen him with the Hofners, the Rick, a Yamaha, a Wal, and Bill Black's original upright bass...but never an Alembic.