So I have finally gotten an 19" rack for my bench!
Here's a tip: If your bottom 19" rack box is massive and boat-anchory enough, you only need the uprights!
I found a 42 unit rack cabinet at my university scrapyard. Seeing as I take the bus and train, just taking it was out of the question. But I really, REALLY wanted to be able to mount up some rack units, so I spent 40 min in the pouring rain unbolting everything and freeing the two front rack uprights. And took them on the bus home.
It was a bizzarre day
Anyway, Ive sold off all of my vintage computer gear; PDP-11, punch-tape punch, reader, racks, CRT terminal, and is now focussing on electronics for physics experiments. On the other side of the bench is a small, very sturdy table for my ultrahigh vacuum system. So far I have everything but the vacuum chamber..