All this talk of Ultrix made me decide to give it a go. After wasting
time and then working out none of the machines I have here support
Ultrix, I decided Simh was the way to go. After a couple of hours of
messing about and checking google, I discovered that Ultrix installs
on RZ disks and Simh doesn't support them. Which is probably why the
cd has been sitting in a box for a couple of years.
About to give up I found a page which shows how to change the
installation program to support RA disks. If anyone wants to give it a
go :
http://minnie.tuhs.org/pipermail/tuhs/2004-November/001090.html
It says it works on 4.3, but it worked on my 4.5 disk. It's installing now.
Dan