Just a quick note to say the machine above installs and runs reasonably.

The "rear" (ATA 100) IDE controller is not recognized.  However, the "front"
(ATA 66) IDE controller is, as is the optical drive IDE controller.

gem0 works, but apparently not from the install kernel, so install off
CD-ROM.

With an HFS+ partition on the factory drive, and a second disk, I ended up
with the boot command:

boot hd:ofwboot.xcf ultra3:0/netbsd

Another note, the distributed XFree86 doesn't support whatever graphics
hardware the machine has.

I haven't tried the second CPU yet ...