Well, the floor plan for a first generation SPARC cpu
was hanging in an
office in a certain east german university in the year 1989. Then certain
changes happened and the massive reverse engineering efforts there stopped.
It is certainly possible to reverse-engineer a _working_ chip. However, I
beleive there are failure modes that would make it impossible in principle
to reverse-engineer a defective chip. So if you find a machine where some
ASIC has failed, you may not be able to reverse-engineer the old one, not
with any tools.
The time to do reverse-engineering (of chips or compulete machiens) is
while said devices are sill operational. Alas doing so can risk damaging
the device in quesiton...
-tony