This Alembic 8-string is not mine, but it has a darker top and it's ex-Entwistle. I played it for half an hour. Killer tone, but a really wide neck. Not just 44mm P neck, but really wide. Haven't measured it.
In the early days of the Dudepit, there was a guy who had bought Entwistle's other Alembic Exploiter -- it had a darker top than this one. He was also looking for a video that had Entwistle using that bass. I located a video that seemed to fit what he described, he bought the video and it turned out to be the one he was looking for. It's been a dozen years and I can't remember but it may have been an instructional video. Now I wonder if it was the Rockschool video.