I've never seen pictures or video footage showing Tom Fowler with his Alembic until I purchased the Zappa DVD 'A Token Of His Extreme' last week. Various internet sources don't seem to agree about this being a legit or semi-bootleg title, but it's really entertaining.
Picture quality is typical VHS to DVD (= not very good but acceptable), sound is pretty good but in stereo. The DVD contains three different (parts of) shows by Zappa & The Mothers from the mid-seventies, with Tom Fowler grooving and mime-dancing (!) with what seems to be a standard point bodied walnut Series I. His bass is prominent in the mix and among the highlights are two performances of the 'One Size Fits All' classic 'Inca Roads'. Highly recommended!
P.S. Unfortunately I can't capture and show screenshots...
Wilfred