Now that I have a beautiful 32M core dump along with a kernel
   in /var/crash, what can be used to get the call stack at the
   time of the crash?

gdb -k netbsd.x netbsd.x.core
   
   It seems to have died somewhere in dead_ something or other,
   but the message flashed by while I was just walking in.

yeah.  charles fixed a bogon in here recently, after i showed
him a crash of mine in dead_something.  try a more recent sup.