The 3B2 was not the same machine as the one in 5ESS,
which
was/is the 3B20D, a fairly large duplexed machine (two processors
that mutually checked each other). The 3B2 was a desktop.
The 3B20D wasn't sold commercially, as far as I know. There
was a 3B20S (multi-cabinet) that at least nominally
was commercially available.
In '93 or '94 I responded to an advertisement by
Temple University (Philadelphia) that they were
giving away for free - U haul - a working 3B20S
system. Figuring it was simply a slightly bigger
brother of the 3B2, I arranged to pick it up and
drove out there.
Imagine my dismay when I discovered it to consist
of four refrigerator-sized cabinets, several
washing-machine disk units, and boxes of spare
parts. Alas, no way that was all going to fit
in my little apartment, not to mention the power
requirements, so I had to turn it down. I hope
they eventually found a good home for it..
Regards,
---corey